fix(securitate): hardening prod — headere, body-cap, non-root, backup

Findings security-review P1/P2 (2026-07-03):
- headere de securitate pe toate raspunsurile (nosniff, X-Frame-Options,
  Referrer-Policy, HSTS doar pe HTTPS) + teste
- body-cap global 10MB ca middleware ASGI pur (413 inainte de parserul
  multipart/JSON; verificarea per-endpoint ramane strat 2)
- imagine Docker non-root (uid 10001), port 8010 aliniat, loguri pe
  volumul /data
- fail-fast la boot cu rar_env=prod fara AUTOPASS_REQUIRE_API_KEY sau
  AUTOPASS_SESSION_SECRET
- compose: env-uri critice obligatorii (:?) ca api/worker sa nu diverga
  tacit; FORWARDED_ALLOW_IPS ca rate-limit-ul sa vada IP-ul real dupa
  Traefik
- signup fara PII in stdout: log_event in loc de print cu email (idem
  notify degradat)
- ratelimit: sterge cheile fara timestamp-uri valide (crestere monotona
  a memoriei pe IP-uri reale)
- backup criptat SQLite (backup online API, gpg AES256) + verificare
  restore + docs/backup.md

Suita completa verde: 1557 passed, 1 skipped (live).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_integrare_api.py

@@ -39,6 +39,9 @@ def client_prod(monkeypatch):
     monkeypatch.setenv("AUTOPASS_DB_PATH", os.path.join(tmp, "t.db"))
     monkeypatch.setenv("AUTOPASS_REQUIRE_API_KEY", "true")
     monkeypatch.setenv("AUTOPASS_RAR_ENV", "prod")
+    # rar_env=prod declanseaza invarianta de startup (validate_prod_invariants,
+    # hardening 2026-07-03): cere si session_secret setat, altfel boot-ul refuza.
+    monkeypatch.setenv("AUTOPASS_SESSION_SECRET", "x" * 32)
     from app.config import get_settings
     get_settings.cache_clear()
     from app.main import app