fix(web-ui): display all human-facing timestamps in Asia/Jerusalem (deterministic)

Storage stays UTC (DB TIMESTAMPTZ, API ISO-UTC) — only the display layer is
localized, and now deterministically: every timestamp renders pinned to
Asia/Jerusalem via a single Intl-based formatter, so SSR (UTC container) and
the browser agree on any runtime. No layout/visible-format change — only the tz.

- New single date formatter web-ui/src/lib/format-date.ts (G2): formatDate /
  formatDateShort / formatDateLong / formatDateTime / formatDateTimeFull /
  formatTime / formatIsoDate + Israel helpers getIsraelYear / israelDayKey /
  israelMidnightMs / israelParts + formatRelative (long/short/tight wording).
- Routed all ad-hoc toLocaleDateString/toLocaleTimeString/toLocaleString +
  hand-rolled new Date(...).get*() / toISOString().slice(0,10) timestamp call
  sites (30 files) through it. Number toLocaleString left untouched.
- Spec: added INV-UI9 to docs/spec/X6 (UTC storage, Asia/Jerusalem display).

Display-only; no layout/design/IA change → Claude Design gate N/A.
Invariants: G2 (single date formatter, no parallel ad-hoc formatting), INV-UI9.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web-ui/src/components/cases/cases-table.tsx

@@ -24,32 +24,16 @@ import {
 import { StatusBadge } from "@/components/cases/status-badge";
 import { isBlamSubtype } from "@/lib/practice-area";
 import type { Case } from "@/lib/api/cases";
+import { formatDate, israelMidnightMs, todayIsraelMidnightMs } from "@/lib/format-date";
 
-function formatDate(iso?: string) {
-  if (!iso) return "—";
-  try {
-    return new Date(iso).toLocaleDateString("he-IL", {
-      day: "2-digit",
-      month: "2-digit",
-      year: "numeric",
-    });
-  } catch {
-    return iso;
-  }
-}
-
-/** Midnight today, in ms — the pivot between an upcoming and a past hearing. */
+/** Midnight today in Israel time, in ms — pivot between an upcoming and a past hearing. */
 function startOfToday() {
-  const d = new Date();
-  d.setHours(0, 0, 0, 0);
-  return d.getTime();
+  return todayIsraelMidnightMs();
 }
 
-/** Day-precision ms for a hearing date, or null when absent/unparseable. */
+/** Day-precision ms (Israel time) for a hearing date, or null when absent/unparseable. */
 function hearingMs(iso?: string | null): number | null {
-  if (!iso) return null;
-  const t = new Date(iso).setHours(0, 0, 0, 0);
-  return Number.isNaN(t) ? null : t;
+  return israelMidnightMs(iso);
 }
 
 type HearingClass = "soon" | "upcoming" | "past" | "none";