fix(verfahrensablauf): m/paliad#59 — restore click-to-edit on timeline dates

Per-rule due dates on /tools/verfahrensablauf were rendered as plain
spans with no `frist-date-edit` attrs and no delegated click handler,
so clicking a date did nothing (m's "the timeline dates seem to be fix,
nothing happens when I click on a date"). The wiring existed on
/tools/fristenrechner but had never been mirrored onto the abstract-
browse surface introduced in t-paliad-179.

Fix: lift the inline date editor + delegated click wiring out of
fristenrechner.ts into views/verfahrensablauf-core.ts so both pages
share one implementation:

  - openInlineDateEditor(span, onCommit) — swaps the date span for
    a `<input type=date>`, commits on blur/Enter, cancels on Escape,
    fires `onCommit(ruleCode, newValue)` ("" = revert).
  - wireDateEditClicks(container, onCommit) — idempotent delegated
    click + keyboard handler that resolves `.frist-date-edit
    [data-rule-code]` and opens the editor. Survives innerHTML
    rewrites because the listener lives on the container.

verfahrensablauf.ts now:
  - Owns its own anchorOverrides Map (cleared when proceeding-type
    changes — overrides for one proceeding don't apply to another).
  - Forwards overrides in calculateDeadlines() so downstream rules
    re-anchor on the user's date.
  - Passes `editable: true` to renderColumnsBody + renderTimelineBody.
  - Calls wireDateEditClicks() once on #timeline-container in
    DOMContentLoaded.

fristenrechner.ts shrinks: openInlineDateEditor + the inline click /
keydown blocks are replaced by an `onDateEditCommit` callback handed
to the shared wireDateEditClicks(). No behaviour change there.

Regression test: views/verfahrensablauf-core.test.ts pins the
editable→`data-rule-code` contract on `deadlineCardHtml` so a future
refactor that drops the attrs fails loudly instead of silently
breaking click-to-edit on both pages.

frontend/src/client/fristenrechner.ts

@@ -2,11 +2,11 @@
 // 3-step wizard: select proceeding -> enter date -> view timeline
 //
 // Rendering primitives (renderTimelineBody / renderColumnsBody /
-// deadlineCardHtml / formatDate / partyBadge / court picker) live in
-// `./views/verfahrensablauf-core` and are shared with the
-// /tools/verfahrensablauf page (t-paliad-179 Slice 1). This module owns
-// the Step1/2/3a wizard, Pathway A/B, Akte save flow, anchor-override
-// click-to-edit — none of which Verfahrensablauf wants.
+// deadlineCardHtml / formatDate / partyBadge / court picker / inline
+// date editor) live in `./views/verfahrensablauf-core` and are shared
+// with /tools/verfahrensablauf. This module owns the Step1/2/3a
+// wizard, Pathway A/B, Akte save flow — none of which Verfahrensablauf
+// wants.
 
 import { initI18n, t, tDyn, getLang, onLangChange } from "./i18n";
 import { initSidebar } from "./sidebar";
@@ -22,6 +22,7 @@ import {
   priorityRendering,
   renderColumnsBody,
   renderTimelineBody,
+  wireDateEditClicks,
 } from "./views/verfahrensablauf-core";
 
 let lastResponse: DeadlineResponse | null = null;
@@ -430,54 +431,21 @@ function renderProcedureResults(data: DeadlineResponse) {
   applyPendingFocus();
 }
 
-// openInlineDateEditor swaps the date span for a date input. On commit
-// (blur or Enter), the override is recorded and the timeline re-fetched.
-// On Escape, the editor closes without changing anything. An empty
-// commit clears the override (lets the user revert to the calculated
-// date or to the IsCourtSet placeholder).
-function openInlineDateEditor(span: HTMLElement) {
-  const ruleCode = span.dataset.ruleCode!;
-  const current = span.dataset.currentDate || anchorOverrides.get(ruleCode) || "";
-  const editor = document.createElement("input");
-  editor.type = "date";
-  editor.className = "frist-date-edit-input";
-  editor.value = current;
-
-  const commit = (newValue: string) => {
-    if (newValue === "") {
-      anchorOverrides.delete(ruleCode);
-    } else {
-      anchorOverrides.set(ruleCode, newValue);
-    }
-    void calculate();
-  };
-
-  const cancel = () => {
-    editor.replaceWith(span);
-  };
-
-  editor.addEventListener("blur", () => {
-    if (editor.value !== current) commit(editor.value);
-    else cancel();
-  });
-  editor.addEventListener("keydown", (e) => {
-    const ke = e as KeyboardEvent;
-    if (ke.key === "Enter") {
-      e.preventDefault();
-      editor.blur();
-    } else if (ke.key === "Escape") {
-      e.preventDefault();
-      cancel();
-    }
-  });
-
-  span.replaceWith(editor);
-  editor.focus();
-  if (editor.value) editor.select();
+// onDateEditCommit is the click-to-edit callback handed to the shared
+// wireDateEditClicks() helper: persist the per-rule override (empty value
+// clears it) then recompute so downstream rules re-anchor.
+function onDateEditCommit(ruleCode: string, newValue: string) {
+  if (newValue === "") {
+    anchorOverrides.delete(ruleCode);
+  } else {
+    anchorOverrides.set(ruleCode, newValue);
+  }
+  void calculate();
 }
 
-// deadlineCardHtml / renderTimelineBody / renderColumnsBody moved to
-// ./views/verfahrensablauf-core (t-paliad-179 Slice 1).
+// deadlineCardHtml / renderTimelineBody / renderColumnsBody /
+// openInlineDateEditor / wireDateEditClicks moved to
+// ./views/verfahrensablauf-core.
 
 function reset() {
   selectedType = "";
@@ -648,21 +616,7 @@ document.addEventListener("DOMContentLoaded", () => {
   // rules re-anchor on the user's date. Delegated on the container so
   // it survives renderProcedureResults() innerHTML rewrites.
   const timelineContainer = document.getElementById("timeline-container");
-  if (timelineContainer) {
-    timelineContainer.addEventListener("click", (e) => {
-      const target = (e.target as HTMLElement).closest<HTMLElement>(".frist-date-edit");
-      if (!target || !target.dataset.ruleCode) return;
-      openInlineDateEditor(target);
-    });
-    timelineContainer.addEventListener("keydown", (e) => {
-      const ke = e as KeyboardEvent;
-      if (ke.key !== "Enter" && ke.key !== " ") return;
-      const target = (e.target as HTMLElement).closest<HTMLElement>(".frist-date-edit");
-      if (!target || !target.dataset.ruleCode) return;
-      e.preventDefault();
-      openInlineDateEditor(target);
-    });
-  }
+  if (timelineContainer) wireDateEditClicks(timelineContainer, onDateEditCommit);
 
   // Reset button
   document.getElementById("reset-btn")!.addEventListener("click", reset);

frontend/src/client/verfahrensablauf.ts

@@ -17,11 +17,21 @@ import {
   populateCourtPicker,
   renderColumnsBody,
   renderTimelineBody,
+  wireDateEditClicks,
 } from "./views/verfahrensablauf-core";
 
 let selectedType = "";
 let lastResponse: DeadlineResponse | null = null;
 
+// Per-rule anchor overrides set by the click-to-edit affordance on
+// timeline / column date cells. Posted as `anchorOverrides` to the
+// /api/tools/fristenrechner calc so downstream rules re-anchor off the
+// user's chosen date. Cleared whenever the trigger changes (proceeding,
+// trigger date, flag toggle) so a fresh calc starts unanchored — same
+// semantic as /tools/fristenrechner.
+const anchorOverrides = new Map<string, string>();
+function clearAnchorOverrides() { anchorOverrides.clear(); }
+
 type ProcedureView = "timeline" | "columns";
 let procedureView: ProcedureView = "columns";
 
@@ -125,10 +135,14 @@ async function doCalc() {
     ? courtPicker.value
     : "";
 
+  const overrides: Record<string, string> = {};
+  for (const [code, date] of anchorOverrides) overrides[code] = date;
+
   const data = await calculateDeadlines({
     proceedingType: selectedType,
     triggerDate,
     flags: readFlags(),
+    anchorOverrides: overrides,
     courtId,
   });
   if (seq !== calcSeq) return;
@@ -180,8 +194,8 @@ function renderResults(data: DeadlineResponse) {
   </div>`;
 
   const bodyHtml = procedureView === "columns"
-    ? renderColumnsBody(data, { showNotes })
-    : renderTimelineBody(data, { showParty: true, showNotes });
+    ? renderColumnsBody(data, { editable: true, showNotes })
+    : renderTimelineBody(data, { showParty: true, editable: true, showNotes });
 
   container.innerHTML = headerHtml + bodyHtml;
   if (printBtn) printBtn.style.display = "block";
@@ -229,7 +243,12 @@ function syncInfAmendEnabled() {
 function selectProceeding(btn: HTMLButtonElement) {
   document.querySelectorAll(".proceeding-btn").forEach((b) => b.classList.remove("active"));
   btn.classList.add("active");
-  selectedType = btn.dataset.code || "";
+  const nextType = btn.dataset.code || "";
+  // Different proceeding tree → previously-set overrides reference
+  // rule codes that don't exist in the new tree. Clear before the
+  // next calc so the fresh proceeding starts unanchored.
+  if (selectedType !== nextType) clearAnchorOverrides();
+  selectedType = nextType;
 
   // Trigger-event label fires from the calc response (root rule).
   // Until step 3 renders, fall back to an em-dash placeholder.
@@ -312,6 +331,21 @@ document.addEventListener("DOMContentLoaded", () => {
 
   document.getElementById("fristen-print-btn")?.addEventListener("click", () => window.print());
 
+  // Click-to-edit on timeline / column date cells — same delegated
+  // pattern as /tools/fristenrechner. Survives renderResults()'s
+  // innerHTML rewrites because the listener lives on the container.
+  const timelineContainer = document.getElementById("timeline-container");
+  if (timelineContainer) {
+    wireDateEditClicks(timelineContainer, (ruleCode, newValue) => {
+      if (newValue === "") {
+        anchorOverrides.delete(ruleCode);
+      } else {
+        anchorOverrides.set(ruleCode, newValue);
+      }
+      scheduleCalc(0);
+    });
+  }
+
   // Notes toggle — restores last preference on load + re-renders when
   // the user flips it. Lives in the same toggle bar as the view picker.
   const notesShowCb = document.getElementById("fristen-notes-show") as HTMLInputElement | null;

frontend/src/client/views/verfahrensablauf-core.test.ts

@@ -0,0 +1,67 @@
+import { describe, expect, test } from "bun:test";
+import {
+  type CalculatedDeadline,
+  deadlineCardHtml,
+} from "./verfahrensablauf-core";
+
+// Regression tests for the editable→click-to-edit wiring on timeline date
+// cells (m/paliad#59). When CardOpts.editable=true the card renderer must
+// emit `class="… frist-date-edit"` with `data-rule-code` + `data-current-
+// date` on the date span. Pages then attach a delegated click handler that
+// resolves that selector to swap in an inline `<input type="date">`. If a
+// future refactor drops the attrs, /tools/verfahrensablauf and
+// /tools/fristenrechner both silently lose click-to-edit (no script error,
+// nothing happens on click). These tests pin the contract.
+//
+// Fixture leaves ruleRef/legalSource* empty so deadlineCardHtml stays
+// inside its non-DOM code paths (escHtml is DOM-backed and bun test runs
+// in plain Node without jsdom).
+
+const dl = (overrides: Partial<CalculatedDeadline> = {}): CalculatedDeadline => ({
+  code: "upc-rop-12",
+  name: "Klageerwiderung",
+  nameEN: "Statement of Defence",
+  party: "defendant",
+  priority: "mandatory",
+  ruleRef: "",
+  dueDate: "2026-07-15",
+  originalDate: "2026-07-15",
+  wasAdjusted: false,
+  isRootEvent: false,
+  isCourtSet: false,
+  ...overrides,
+});
+
+describe("deadlineCardHtml — editable=true emits click-to-edit attrs", () => {
+  test("date span carries frist-date-edit class + data-rule-code + data-current-date", () => {
+    const html = deadlineCardHtml(dl(), { showParty: true, editable: true });
+    expect(html).toContain('class="timeline-date frist-date-edit"');
+    expect(html).toContain('data-rule-code="upc-rop-12"');
+    expect(html).toContain('data-current-date="2026-07-15"');
+    expect(html).toContain('role="button"');
+    expect(html).toContain('tabindex="0"');
+  });
+
+  test("editable=false (default) emits the date span without click-to-edit attrs", () => {
+    const html = deadlineCardHtml(dl(), { showParty: true });
+    expect(html).toContain("timeline-date");
+    expect(html).not.toContain("data-rule-code=");
+    expect(html).not.toContain('role="button"');
+  });
+
+  test("root event suppresses editable even when editable=true (root has no override semantic)", () => {
+    const html = deadlineCardHtml(dl({ isRootEvent: true }), { showParty: true, editable: true });
+    expect(html).not.toContain("data-rule-code=");
+  });
+
+  test("isCourtSet renders the court-set placeholder with click-to-edit so users can pin a real date", () => {
+    const html = deadlineCardHtml(dl({ isCourtSet: true }), { showParty: true, editable: true });
+    expect(html).toContain("timeline-court-set frist-date-edit");
+    expect(html).toContain('data-rule-code="upc-rop-12"');
+  });
+
+  test("empty rule code with editable=true still suppresses click-to-edit (no anchor target)", () => {
+    const html = deadlineCardHtml(dl({ code: "" }), { showParty: true, editable: true });
+    expect(html).not.toContain("data-rule-code=");
+  });
+});

frontend/src/client/views/verfahrensablauf-core.ts

@@ -299,6 +299,87 @@ export function deadlineCardHtml(dl: CalculatedDeadline, opts: CardOpts): string
     ${notesBlock}`;
 }
 
+// ─── inline date editor (click-to-edit per-rule due date) ────────────────
+//
+// The renderer emits `<span class="frist-date-edit" data-rule-code="…"
+// data-current-date="YYYY-MM-DD" role="button" tabindex="0">…</span>` when
+// CardOpts.editable is true. Pages call wireDateEditClicks() on their
+// result container once, and the delegated click/keydown handlers swap a
+// clicked span for a `<input type="date">` editor via openInlineDateEditor.
+// The caller's onCommit callback receives (ruleCode, newValue) — an empty
+// newValue means "revert" (clear the anchor override and let the calculator
+// re-project). The actual recompute is the caller's job — they own the
+// anchor-overrides map + the calc dispatch.
+
+export function openInlineDateEditor(
+  span: HTMLElement,
+  onCommit: (ruleCode: string, newValue: string) => void,
+): void {
+  const ruleCode = span.dataset.ruleCode || "";
+  if (!ruleCode) return;
+  const current = span.dataset.currentDate || "";
+  const editor = document.createElement("input");
+  editor.type = "date";
+  editor.className = "frist-date-edit-input";
+  editor.value = current;
+
+  let done = false;
+  const cancel = () => {
+    if (done) return;
+    done = true;
+    editor.replaceWith(span);
+  };
+  const commit = (newValue: string) => {
+    if (done) return;
+    done = true;
+    onCommit(ruleCode, newValue);
+  };
+
+  editor.addEventListener("blur", () => {
+    if (editor.value !== current) commit(editor.value);
+    else cancel();
+  });
+  editor.addEventListener("keydown", (e) => {
+    const ke = e as KeyboardEvent;
+    if (ke.key === "Enter") {
+      e.preventDefault();
+      editor.blur();
+    } else if (ke.key === "Escape") {
+      e.preventDefault();
+      cancel();
+    }
+  });
+
+  span.replaceWith(editor);
+  editor.focus();
+  if (editor.value) editor.select();
+}
+
+// wireDateEditClicks attaches delegated click + keyboard handlers to the
+// timeline result container so click-to-edit survives every innerHTML
+// rewrite the page does on recalc. Idempotent — re-calling on the same
+// container does nothing (the dataset flag short-circuits).
+export function wireDateEditClicks(
+  container: HTMLElement,
+  onCommit: (ruleCode: string, newValue: string) => void,
+): void {
+  if (container.dataset.dateEditWired === "1") return;
+  container.dataset.dateEditWired = "1";
+  container.addEventListener("click", (e) => {
+    const target = (e.target as HTMLElement).closest<HTMLElement>(".frist-date-edit");
+    if (!target || !target.dataset.ruleCode) return;
+    openInlineDateEditor(target, onCommit);
+  });
+  container.addEventListener("keydown", (e) => {
+    const ke = e as KeyboardEvent;
+    if (ke.key !== "Enter" && ke.key !== " ") return;
+    const target = (e.target as HTMLElement).closest<HTMLElement>(".frist-date-edit");
+    if (!target || !target.dataset.ruleCode) return;
+    e.preventDefault();
+    openInlineDateEditor(target, onCommit);
+  });
+}
+
 export function renderTimelineBody(data: DeadlineResponse, opts: CardOpts = { showParty: true }): string {
   let html = '<div class="timeline">';
   for (const dl of data.deadlines) {