feat(citation-verify): frontend "אימות פסיקה" tab in the decision editor (#154)

Frontend half of the citation-verification panel (backend in #323), as the agreed
third tab in /compose — matching the approved X17 mockup 24-citation-verification:

- lib/api/citation-verification.ts: hand-written types + useCitationVerification
  query + useVerifyCitation mutation (POST verify, invalidates the view).
- components/compose/citation-verification-panel.tsx: per legal argument →
  supporting corpus precedents with the cited_by authority chips (אומץ ×N /
  אובחן ×N), the exact supporting_quote, ✓ מאמת / ✗ לא רלוונטי verify actions, a
  per-citation chair-note field, and the per-issue 📡 radar (unlinked digests,
  pointer-only). Summary strip + INV-AH/INV-DIG1 reminders.
- compose page: third tab "אימות פסיקה" alongside עורך הבלוקים / עמדות וטענות.

No api:types regen needed (endpoints return assembled dicts; types hand-written
per the lib/api convention). tsc + eslint clean.

Invariants: INV-AH (writer cites only verified), INV-DIG1 (digest never cited),
G2 (consumes the one backend view). Visual matches the gate-approved mockup.

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

web-ui/src/app/cases/[caseNumber]/compose/page.tsx

@@ -9,6 +9,7 @@ import { Button } from "@/components/ui/button";
 import { Skeleton } from "@/components/ui/skeleton";
 import { SubsectionCard } from "@/components/compose/subsection-card";
 import { PrecedentsSection } from "@/components/compose/precedents-section";
+import { CitationVerificationPanel } from "@/components/compose/citation-verification-panel";
 import { DecisionBlocksPanel } from "@/components/cases/decision-blocks-panel";
 import { Markdown } from "@/components/ui/markdown";
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
@@ -276,6 +277,7 @@ export default function ComposePage({
               <TabsList className="bg-rule-soft/60">
                 <TabsTrigger value="blocks">עורך הבלוקים</TabsTrigger>
                 <TabsTrigger value="positions">עמדות וטענות</TabsTrigger>
+                <TabsTrigger value="verify">אימות פסיקה</TabsTrigger>
               </TabsList>
 
               {/* Tab 1 — the 12-block decision editor (reused DecisionBlocksPanel) */}
@@ -283,6 +285,11 @@ export default function ComposePage({
                 <DecisionBlocksPanel caseNumber={caseNumber} />
               </TabsContent>
 
+              {/* Tab 3 — citation verification: per-argument support + verify gate (#154) */}
+              <TabsContent value="verify" className="mt-5">
+                <CitationVerificationPanel caseNumber={caseNumber} />
+              </TabsContent>
+
               {/* Tab 2 — chair positions on the analyst's threshold-claims + issues */}
               <TabsContent value="positions" className="mt-5">
                 {analysis.isPending ? (