feat: fase 2+3 — expansion masiva multi-perfil + bug fixes + hardening

Fase 2 (expansion):
- Francesca: +6 etapas matematicas (5-10), +7 etapas lectura (3-9), +2 ortografia
- Sebastian: +8 etapas matematicas (4-11), +6 lectura, +3 historia, +3 geografia, +1 banderas
- Nuevas paginas: ortografia, lectura, geografia, matematicas
- ~900 ejercicios nuevos, paridad ~500 por perfil

Fase 3 (bug fixes + hardening):
- Fix: SessionLog auto-create en grade route
- Fix: engine cache (no borrar antes de revisar)
- Fix: FSRS cards actualizadas en flujo curriculum
- Fix: responseMs real (no hardcodeado 3000)
- Fix: options dentro de content en sebastian etapa-1
- Fix: trazo-letra consonantes crash
- Security: execFileSync anti-command-injection en TTS
- DB: 18 cascade deletes + indices + unique constraints
- APIs debug: reset, state, seed
- Docker: espeak-ng + prisma + user/group
- E2E: 23 tests nuevos (curriculum-flow.spec.ts)
- Code review: tailwind colors, middleware dev mode, eslint config

Verificado: tsc exit 0, build exit 0, 61 E2E tests pass

lib/curriculum/engine.ts

@@ -9,25 +9,27 @@ const PROFILE_CURRICULA: Record<string, Record<string, { folder: string; stages:
     numeros: { folder: "numeros", stages: [1, 2, 3, 4, 5, 6, 7, 8] },
   },
   FRANCESCA: {
-    matematicas: { folder: "francesca", stages: [1, 2, 3, 4] },
-    lecturas: { folder: "francesca-lectura", stages: [1, 2] },
+    matematicas: { folder: "francesca", stages: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] },
+    lecturas: { folder: "francesca-lectura", stages: [1, 2, 3, 4, 5, 6, 7, 8, 9] },
+    ortografia: { folder: "francesca-ortografia", stages: [1, 2] },
   },
   SEBASTIAN: {
-    sumas: { folder: "sebastian", stages: [1, 2, 3] },
-    historia: { folder: "sebastian-historia", stages: [1, 2] },
-    banderas: { folder: "sebastian-banderas", stages: [1] },
+    sumas: { folder: "sebastian", stages: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11] },
+    matematicas: { folder: "sebastian", stages: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11] },
+    lectura: { folder: "sebastian-lectura", stages: [1, 2, 3, 4, 5, 6] },
+    historia: { folder: "sebastian-historia", stages: [1, 2, 3, 4, 5] },
+    geografia: { folder: "sebastian-geografia", stages: [1, 2, 3] },
+    banderas: { folder: "sebastian-banderas", stages: [1, 2] },
   },
 }
 
 const curriculumCache: Record<string, Record<string, Stage>> = {}
 
-async function getStagesForProfile(
+export async function getStagesForProfile(
   profile: string,
   topic: string,
 ): Promise<Record<string, Stage>> {
   const key = `${profile}-${topic}`
-  // Clear stale cache on every dev call (Next.js hot-reload shares module-level vars)
-  if (curriculumCache[key]) delete curriculumCache[key]
 
   if (curriculumCache[key]) return curriculumCache[key]