RegWatch backend : FastAPI + Postgres partagé + Docker/CI homelab

- SECRET_KEY et DATABASE_URL externalisés (Vault -> env), plus de secret en dur
- SQLite -> postgres-shared (psycopg2), schéma créé au boot (entrypoint.sh)
- Dockerfile + docker-compose (Watchtower) + .gitea/workflows/build.yml

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

init_db.py

@@ -0,0 +1,27 @@
+from database.database import engine, SessionLocal
+from database.models import Base, User
+from api.auth import get_password_hash
+
+Base.metadata.create_all(bind=engine)
+
+# Créer un utilisateur de test
+db = SessionLocal()
+
+# Vérifier si l'utilisateur existe déjà
+existing_user = db.query(User).filter(User.email == "admin@test.com").first()
+
+if not existing_user:
+    test_user = User(
+        email="admin@test.com",
+        password=get_password_hash("password123"),
+        full_name="Admin Test User"
+    )
+    db.add(test_user)
+    db.commit()
+    print("Test user created: admin@test.com / password123")
+else:
+    print("Test user already exists")
+
+db.close()
+
+print("Database initialized successfully.")