feat(api): filtru perioada data_de/data_pana pe GET /v1/prezentari

data_prestatie traieste in payload_json, nu e coloana SQL: filtrarea se aplica
in Python dupa derivarea prezentarii (fetch scope+status fara LIMIT, filtreaza,
apoi LIMIT dupa filtrare), acelasi pattern deja folosit de dashboard-ul web
(/_fragments/submissions). Extrage helper-ul iso_date_prefix in payload_view.py
ca sa fie partajat intre canalul web si cel API (elimina duplicarea).

Format invalid pe data_de/data_pana -> 422. Fara parametri, comportamentul
raspunsului ramane identic cu inainte.

app/api/v1/router.py

@@ -51,7 +51,7 @@ from ...models import (
     ValidareResult,
 )
 from ...observ import log_event
-from ...payload_view import prezentare_din_payload
+from ...payload_view import iso_date_prefix, prezentare_din_payload
 from ...submissions_admin import (
     SubmissionNotFound,
     SubmissionStateConflict,
@@ -503,12 +503,35 @@ def valideaza_prezentari(
     return ValidareResponse(results=results)
 
 
+def _valida_data_filtru(nume_param: str, valoare: str | None) -> str | None:
+    """Valideaza formatul YYYY-MM-DD al unui parametru de filtrare pe perioada.
+
+    None/gol -> None (filtru inactiv). Format invalid -> 422, consecvent cu restul
+    rutelor API (vezi celelalte `status_code=422` din acest fisier).
+    """
+    v = (valoare or "").strip()
+    if not v:
+        return None
+    try:
+        datetime.strptime(v, "%Y-%m-%d")
+    except ValueError:
+        raise HTTPException(
+            status_code=422,
+            detail=f"{nume_param} trebuie sa fie in format YYYY-MM-DD",
+        )
+    return v
+
+
 @router.get("/prezentari")
 def list_prezentari(
     status: str | None = None,
+    data_de: str | None = None,
+    data_pana: str | None = None,
     limit: int = 100,
     account_id: int = Depends(resolve_account_id),
 ) -> dict:
+    data_de = _valida_data_filtru("data_de", data_de)
+    data_pana = _valida_data_filtru("data_pana", data_pana)
     conn = get_connection()
     try:
         scope_sql, scope_params = account_scope_clause(account_id)
@@ -519,24 +542,49 @@ def list_prezentari(
             "id, status, id_prezentare, rar_status_code, retry_count, "
             "created_at, updated_at, payload_json, rar_env, held"
         )
+        where = [scope_sql]
+        params: list = list(scope_params)
         if status:
+            where.append("status=?")
+            params.append(status)
+        where_sql = " AND ".join(where)
+
+        # data_prestatie traieste in payload_json, nu e coloana SQL (vezi
+        # payload_view.prezentare_din_payload) — nu poate intra in clauza WHERE.
+        # Cu filtru de perioada activ: fetch scope+status FARA LIMIT, filtreaza in
+        # Python dupa derivarea prezentarii, apoi LIMIT-eaza DUPA filtrare (altfel
+        # LIMIT SQL ar trunchia gresit inainte de filtru). Acelasi pattern ca
+        # /_fragments/submissions (dashboard web, app/web/routes.py).
+        filtru_perioada = bool(data_de or data_pana)
+        if filtru_perioada:
             rows = conn.execute(
-                f"SELECT {cols} FROM submissions WHERE {scope_sql} AND status=? "
-                f"ORDER BY id DESC LIMIT ?",
-                scope_params + [status, limit],
+                f"SELECT {cols} FROM submissions WHERE {where_sql} ORDER BY id DESC",
+                params,
             ).fetchall()
         else:
             rows = conn.execute(
-                f"SELECT {cols} FROM submissions WHERE {scope_sql} ORDER BY id DESC LIMIT ?",
-                scope_params + [limit],
+                f"SELECT {cols} FROM submissions WHERE {where_sql} ORDER BY id DESC LIMIT ?",
+                params + [limit],
             ).fetchall()
+
         out = []
         for r in rows:
             d = dict(r)
             # Campuri afisabile derivate din payload (acelasi helper ca dashboardul web);
             # payload_json brut nu se intoarce in raspuns.
-            d["prezentare"] = prezentare_din_payload(d.pop("payload_json", None))
+            prezentare = prezentare_din_payload(d.pop("payload_json", None))
+            if filtru_perioada:
+                d_prefix = iso_date_prefix(prezentare["data_prestatie"])
+                if d_prefix is None:
+                    continue
+                if data_de and d_prefix < data_de:
+                    continue
+                if data_pana and d_prefix > data_pana:
+                    continue
+            d["prezentare"] = prezentare
             out.append(d)
+            if filtru_perioada and len(out) >= limit:
+                break
         return {"submissions": out}
     finally:
         conn.close()