feat(banner): P19 + P20 — Per-Category-Click-Test + Frontend-Drilldown

P19 (consent-tester):
- dp-cookieconsent (TYPO3, Safetykon-Pattern) als CMP-Profil hinzu —
  Selektoren #dp--cookie-statistics/marketing + a.cc-allow Save-Button
- Neues Signal provider_details_visible: nach Kategorie-Toggle prueft
  Playwright ob im Banner sichtbare Provider-/Cookie-Detail-Elemente
  erscheinen. Bei dp-cookieconsent (Banner ohne Listing) immer False
  -> HIGH-Violation "Kategorie zeigt keine Provider-/Cookie-Details —
  Nutzer kann nicht informiert einwilligen (Art. 7 Abs. 1 DSGVO)"
- main.py serialisiert provider_details_visible + cookies_set pro Kategorie

P20 (Frontend-Drilldown):
- Backend: check_payloads-Tabelle um Spalte 'banner' (JSON) — voller
  banner_result persistiert (vorher nur in-memory). ALTER TABLE
  Migration idempotent.
- Neuer Endpoint GET /api/compliance/agent/banner/<check_id> — liefert
  Quality-Score, Phases, Category-Tests, Banner-Checks, alle 46
  structured_checks.
- Frontend: BannerTab im /sdk/agent/audit/<id> mit Quality-Cards,
  3-Phasen-Cookie-Tabelle, Per-Category-Listing (mit P19-Signal
  rot/gruen), Banner-Verstoesse + Rechtsgrundlagen, 46-Check-Drilldown
  filterbar nach Severity.
- Tab-Switcher in page.tsx um "Cookie-Banner-Analyse" erweitert.
- Bonus: 2 alte route.ts auf Next.js 15 Promise-params umgestellt
  (Build-Fix).

Plus: Critical-Findings-Block nutzt provider_details_visible als
primaeres Signal statt nur tracking_services-Anzahl.

Smoke-Test Safetykon: 4 Critical Findings im Mail, banner-Endpoint
liefert 46 checks + 3 phases + 2 categories mit provider_details_visible=False.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

admin-compliance/app/sdk/agent/audit/[checkId]/page.tsx

@@ -3,6 +3,7 @@
 import React, { useEffect, useState, useMemo } from 'react'
 import { use as useUnwrap } from 'react'
 import FindingsTab from './FindingsTab'
+import BannerTab from './BannerTab'
 
 type MCRow = {
   id: number
@@ -92,7 +93,7 @@ export default function AuditPage(
   const [filterReg, setFilterReg] = useState<string>('')
   const [filterDoc, setFilterDoc] = useState<string>('')
   const [expanded, setExpanded] = useState<number | null>(null)
-  const [tab, setTab] = useState<'mc' | 'all'>('all')
+  const [tab, setTab] = useState<'mc' | 'all' | 'banner'>('all')
 
   useEffect(() => {
     let cancelled = false
@@ -155,6 +156,7 @@ export default function AuditPage(
       <div className="flex gap-2 border-b border-gray-200">
         {([
           { key: 'all', label: 'Voll-Audit (alle Findings)' },
+          { key: 'banner', label: 'Cookie-Banner-Analyse' },
           { key: 'mc', label: 'Nur MC-Scorecard' },
         ] as const).map(t => (
           <button key={t.key}
@@ -168,6 +170,7 @@ export default function AuditPage(
       </div>
 
       {tab === 'all' && <FindingsTab checkId={checkId} />}
+      {tab === 'banner' && <BannerTab checkId={checkId} />}
 
       {tab === 'mc' && <>
       {/* Scorecard */}