Executive Meetings: inline editing, drag reorder, and current-meeting highlight

Implements Task #122 — four features on the Executive Meetings schedule:
1. Word-like inline editing of meeting title and attendee names with bold,
   italic, underline, color, font-family, font-size, and text-align controls
   (Tiptap-backed EditableCell + FormattingToolbar).
2. Drag-to-reorder column headers (dnd-kit), persisted in the existing
   em-schedule-cols-v1 storage key. Old up/down buttons removed.
3. Drag-to-reorder rows within a day. New POST /api/executive-meetings/reorder
   endpoint permutes daily_number + start/end times in a single transaction
   using a two-phase negative→final assignment that respects the
   (date, daily_number) UNIQUE constraint and survives partial-day reorders.
   Audit-logged and role-guarded.
4. Highlight the meeting whose start/end window is "now", refreshed every
   60 s. Toggle and color picker live in the customize popover and persist
   to localStorage (em-current-meeting-highlight-v1).

Backend changes
- Widened titleAr / titleEn / attendees.name to text.
- New artifacts/api-server/src/lib/sanitize.ts with an allowlist for
  inline tags + safe inline styles. Applied to POST, PATCH, PUT-attendees,
  duplicate, reorder, and applyApprovedRequest (add_attendee) paths so
  rich text round-trips safely.
- Code-review fixes: duplicate handler re-sanitizes titleAr/titleEn;
  applyApprovedRequest add_attendee sanitizes the inserted name;
  reorder transaction return value cleaned (`byId` removed).
- 5 new tests cover sanitization stripping, reorder happy path, cross-day
  rejection, permission denial, and applyApprovedRequest sanitization.
  Pre-existing app_permissions failures are unrelated (tracked by #126/#127).

Frontend changes
- artifacts/tx-os/src/components/editable-cell.tsx with FormattingToolbar
  (custom FontSize Tiptap extension + @tiptap/extension-text-align).
- ScheduleSection wires saveTitle, saveAttendeeName, reorder mutation
  (optimistic with revert on error), highlight tick, and HighlightPrefs.
- New SortableHeader component for column drag.
- AttendeesCell passes the original attendee index to PUT writes so edits
  reach the right row even after grouping into virtual/internal/external.
- Print page renders sanitized rich text via dangerouslySetInnerHTML on
  names and titles; attendee.title is rendered as a plain text node (XSS).
- Translation keys added in ar.json and en.json.

artifacts/tx-os/src/pages/executive-meetings.tsx

@@ -726,13 +726,18 @@ function ScheduleSection({
     writeJsonToStorage(HIGHLIGHT_STORAGE_KEY, highlightPrefs);
   }, [highlightPrefs]);
 
-  // 60-second tick to recompute the "current" meeting highlight. Refreshing
-  // less frequently than the minute boundary risks the highlight visibly
-  // lagging when one meeting ends and another starts.
   const [nowTick, setNowTick] = useState(() => Date.now());
   useEffect(() => {
-    const id = setInterval(() => setNowTick(Date.now()), 60_000);
-    return () => clearInterval(id);
+    let intervalId: ReturnType<typeof setInterval> | null = null;
+    const msToNextMinute = 60_000 - (Date.now() % 60_000);
+    const timeoutId = setTimeout(() => {
+      setNowTick(Date.now());
+      intervalId = setInterval(() => setNowTick(Date.now()), 60_000);
+    }, msToNextMinute);
+    return () => {
+      clearTimeout(timeoutId);
+      if (intervalId) clearInterval(intervalId);
+    };
   }, []);
 
   const currentMeetingId = useMemo(