feat(scheduler,conversations,api): cron and schedule in the gateway tz, job runs persisted

src/beaver_gateway/storage/models.py

@@ -360,6 +360,32 @@ class RateLimit(SQLModel, table=True):
     )
 
 
+class JobRunRecord(SQLModel, table=True):
+    """One finished run of a scheduler job (§3.6): what fired it, how it ended.
+
+    ``error`` keeps the head of the traceback of a failed run; ``payload``
+    is the trigger's data (``{}`` for cron) and should stay small.
+    """
+
+    __tablename__ = "job_runs"
+
+    id: int | None = Field(default=None, primary_key=True)
+    job: str = Field(index=True)
+    trigger: str
+    started_at: datetime
+    finished_at: datetime
+    status: str
+    error: str | None = Field(default=None)
+    payload: dict[str, Any] = Field(
+        default_factory=dict,
+        sa_column=Column(
+            JSON().with_variant(JSONB(), "postgresql"),
+            nullable=False,
+            server_default=text("'{}'"),
+        ),
+    )
+
+
 __all__ = [
     "AuditLog",
     "Conversation",
@@ -367,6 +393,7 @@ __all__ = [
     "ConversationMessage",
     "Delivery",
     "InjectQueueItem",
+    "JobRunRecord",
     "RateLimit",
     "TelegramUpdate",
     "Token",