fix(audit): nettoyage accès, garde-fous build, unification quotas

Semaine 1 — fuites et accès :
- /archive rendu accessible via sidebar (était invisible)
- Suppression pages orphelines : /chat, /graph, /support, test-title-suggestions
- Fixes i18n : search-modal (clé non interpolée), sidebar tooltips, export PDF
- 15 locales mises à jour

Semaine 2 — garde-fous :
- 8 erreurs TS fixees → ignoreBuildErrors: false (build type-safe)
- reactStrictMode: true (dev-only, zero impact prod)
- reserveUsageOrThrow → wrapper deprecie vers reserveAiUsageOrThrow
- auth-guard.ts : requireAuthOrResponse() + requireAdminOrResponse()

Tests 212/212 | Lint 0 erreur | Build OK | tsc 0 erreur

memento-note/lib/entitlements.ts

@@ -7,6 +7,7 @@ import {
   parseRedisInt,
   isValidFeature,
   VALID_FEATURES,
+  type FeatureName,
 } from './quota-utils';
 import {
   getLimitAsync,
@@ -261,6 +262,11 @@ export async function getEffectiveTier(
   return 'BASIC';
 }
 
+// NOTE: canUseFeature reads the old per-feature Redis counters + UsageLog table.
+// Since reserveUsageOrThrow now delegates to the unified credits engine (AiCreditAccount),
+// these counters are no longer written to — this function returns stale/zero usage data.
+// Only caller: checkEntitlementOrThrow → app/api/ai/tags/route.ts (pre-check that always passes).
+// Actual enforcement happens via reserveAiUsageOrThrow at the debit site.
 export async function canUseFeature(
   userId: string,
   feature: string,
@@ -365,10 +371,10 @@ function featureToAiLane(feature: string): 'chat' | 'tags' | 'embedding' {
 }
 
 /**
- * Réserve des crédits globaux (modèle A).
+ * @deprecated Use `reserveAiUsageOrThrow` from `@/lib/ai-quota` instead.
+ * Thin wrapper kept for backward compat — delegates to the unified credits engine.
  * `amount` = coût en crédits (ex. slides multi-étapes : 1+N).
  * Si l'utilisateur a une clé perso (BYOK) pour la voie concernée, aucun débit.
- * Conserve le nom historique pour ne pas casser tous les appelants.
  */
 export async function reserveUsageOrThrow(
   userId: string,
@@ -378,17 +384,8 @@ export async function reserveUsageOrThrow(
   if (!isValidFeature(feature)) {
     throw new QuotaExceededError('PRO', feature, 0, 0, false, { currentTier: 'BASIC' });
   }
-
-  const { getSystemConfig } = await import('@/lib/config');
-  const { willUseByokForLane } = await import('@/lib/ai/provider-for-user');
-  const config = await getSystemConfig();
-  const lane = featureToAiLane(feature);
-  const { usedByok } = await willUseByokForLane(lane, config, userId);
-  if (usedByok) return;
-
-  const { reserveCreditsOrThrow, resolveCreditCost } = await import('@/lib/credits');
-  const cost = resolveCreditCost(feature, { amount });
-  await reserveCreditsOrThrow(userId, cost, { feature });
+  const { reserveAiUsageOrThrow } = await import('@/lib/ai-quota');
+  await reserveAiUsageOrThrow(userId, feature as FeatureName, { amount });
 }
 
 /** Units charged for one multi-step slide generation (outline + per-slide expand). */