feat(advisor): v3 Clarity Gate — Case model + clarify/answer contract, [n] citations

Builds the FE against the SDK<->FE Clarity-Gate contract (board 2026-07-01 /
advisor-clarity-gate-contract). The advisor is now a CASE, not a chat:
- Request {question, context?}; response {mode: clarify|answer, clarity, general_answer,
  answer, evidence, citations, visual_evidence, footnotes}.
- clarify mode: short L1 general answer (marked "allgemeine Definition, ohne Rechtsquelle")
  + domain context chips; picking a chip re-runs the case scoped (-> answer).
- answer mode: markdown answer with clickable [n] citation markers coupled to evidence
  cards (highlight + scroll), evidence grouped by document family, visual_evidence
  (visual_type), footnotes, honest summary counts (no trust score).
- FE never parses the answer for structure — only the deliberate [n] markers, mapped via
  citations[]. New: contract.ts, useAdvisorCase, useCitationHighlight, ClarifyView,
  EvidenceUnitCard, VisualEvidencePane, CaseView. Removed the v2 stream/chat components.

NOT deployed: FE shape-switch (JSON modes) must deploy TOGETHER with the SDK endpoint
delivering the contract (board deploy-coupling). Proxy/route.ts unchanged (SDK-owned).
tsc clean, 16 vitest (incl. clarify+answer fixtures), check-loc 0.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

admin-compliance/components/sdk/advisor/FootnotesPane.tsx

@@ -1,24 +1,26 @@
 'use client'
 
 import { Hash } from 'lucide-react'
-import type { FootnoteUnit } from '@/lib/sdk/advisor/evidence'
+import type { Footnote } from '@/lib/sdk/advisor/contract'
 import { PaneHeader } from './PaneHeader'
 
 /** Footnotes pane (C-FN) — rendered only when present. */
-export function FootnotesPane({ footnotes }: { footnotes: FootnoteUnit[] }) {
+export function FootnotesPane({ footnotes }: { footnotes: Footnote[] }) {
   if (footnotes.length === 0) return null
   return (
     <section>
       <PaneHeader icon={<Hash className="h-3.5 w-3.5 text-gray-500" />} title="Fußnoten" count={footnotes.length} />
       <div className="space-y-1">
-        {footnotes.map((fn) => (
-          <div key={fn.id} className="rounded-md border border-gray-200 bg-white p-2 text-[11px]">
-            <span className="font-semibold text-gray-900">{fn.ref}</span>
-            <span className="text-gray-400">
-              {' · '}
-              {fn.source.short}
-              {fn.section ? ` / ${fn.section}` : ''}
-            </span>
+        {footnotes.map((fn, i) => (
+          <div key={fn.footnote_id || i} className="rounded-md border border-gray-200 bg-white p-2 text-[11px]">
+            <span className="font-semibold text-gray-900">{fn.ref || `Fußnote ${i + 1}`}</span>
+            {(fn.document || fn.section) && (
+              <span className="text-gray-400">
+                {' · '}
+                {fn.document}
+                {fn.section ? ` / ${fn.section}` : ''}
+              </span>
+            )}
             {fn.text && <p className="mt-0.5 text-gray-600">{fn.text}</p>}
           </div>
         ))}