feat(5.20): US-004/005/006/009 ingestie+API+worker+import pe mediu RAR

US-004: rezolva_rar_env (cerere>default cont>ancora globala) + MediuIndisponibil
+ cod RAR_MEDIU_INDISPONIBIL.
US-005: camp rar_env pe POST /v1/prezentari + /valideaza (Literal), echo in
SubmissionResult/ValidareResult/GET, build_key + INSERT env-aware.
US-006: AccountSessions re-cheiat (account_id, rar_env); RarClient base_url per
env; creds din slotul env; purge + recover_orphans scoped pe env (E1/1a, 1b/E6);
claim_one propaga rar_env (1c/E8); keepalive pe ancora globala (M2).
US-009: selector mediu la import (>=2 medii), eticheta la 1, banner la 0; commit
seteaza rar_env pe submissions.

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

tests/test_import_e2e.py

@@ -511,7 +511,7 @@ class TestE2EMixedQueue:
 
         # 4. Worker cu MockRar injectat prin AccountSessions (simulam bucla worker)
         mock_rar = MockRar(id_prezentare=66001, login_token="tok-mock")
-        monkeypatch.setattr(w, "RarClient", lambda settings=None: mock_rar)
+        monkeypatch.setattr(w, "RarClient", lambda settings=None, **kw: mock_rar)
 
         sessions = w.AccountSessions(settings)
         conn = get_connection()
@@ -595,7 +595,7 @@ class TestE2EMixedQueue:
             conn.close()
 
         mock_rar = MockRar(id_prezentare=77777)
-        monkeypatch.setattr(w, "RarClient", lambda settings=None: mock_rar)
+        monkeypatch.setattr(w, "RarClient", lambda settings=None, **kw: mock_rar)
 
         sessions = w.AccountSessions(settings)
         conn = get_connection()