fix: revision completa de rutas Docker, logica SQL y configuracion

Backend Go:
- backend/cmd/server/main.go: ruta wiki_images configurable via WIKI_IMAGES_PATH
- backend/cmd/wiki_worker/main.go: default /opt/rss2 en lugar de /app, leer env
- workers/ctranslator_worker.py: default CT2_MODEL_PATH /opt/rss2 en lugar de /app
- workers/llm_categorizer_worker.py: default LLM_MODEL_PATH /opt/rss2
- workers/{langdetect,simple_translator,translation_scheduler}.py: DB_HOST default 'localhost' en lugar de 'db' (hostname Docker)

SQL / esquema:
- poc/seed.sql: corregir logica de auto-traducciones ES (id LIKE md5() era incorrecto)
- init-db/06-tags.sql: eliminar columna wiki_checked duplicada

Documentacion y configuracion:
- docs/DEPLOY_DEBIAN.md: usar ct2-transformers-converter (lo que usa el worker real)
- deploy/debian/env.example: agregar WIKI_IMAGES_PATH
- deploy/debian/systemd/rss2-cluster.service: agregar HF_HOME faltante
- deploy/debian/install.sh: comparacion numerica correcta de version Go
- scripts/generate_secure_credentials.sh: ruta CT2_MODEL_PATH corregida
- frontend/nginx.conf: advertencia de que es configuracion Docker legacy
- docs/QUICKSTART_LLM.md: nota de deprecacion Docker
- README.md: renombrar backend-go a backend en diagrama

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

workers/ctranslator_worker.py

@@ -62,7 +62,7 @@ BATCH_SIZE = _env_int("TRANSLATOR_BATCH", 8)
 MAX_SRC_TOKENS = _env_int("MAX_SRC_TOKENS", 512)
 MAX_NEW_TOKENS = _env_int("MAX_NEW_TOKENS", 512)
 
-CT2_MODEL_PATH = _env_str("CT2_MODEL_PATH", "/app/models/nllb-ct2")
+CT2_MODEL_PATH = _env_str("CT2_MODEL_PATH", "/opt/rss2/models/nllb-ct2")
 CT2_DEVICE = _env_str("CT2_DEVICE", "cpu")
 CT2_COMPUTE_TYPE = _env_str("CT2_COMPUTE_TYPE", "int8")
 UNIVERSAL_MODEL = _env_str("UNIVERSAL_MODEL", "facebook/nllb-200-distilled-600M")