feat(python/robomp): implemented has_authorized_impl_event in the

- Implement `has_authorized_impl_event` in the database to retrieve historical authorization state.
- Update `_enforce_impl_authorization` to permit actions if prior events on the issue provided implementation authorization.
- Normalize maintainer logins by stripping `[bot]` suffixes and allow match-regex to ignore them.

python/robomp/src/db.py

@@ -607,6 +607,26 @@ class Database:
             last_error=row["last_error"],
         )
 
+    def has_authorized_impl_event(self, issue_key: str) -> bool:
+        """Return whether a non-skipped event on this issue carried implementation authorization."""
+        with self._lock:
+            rows = self._conn.execute(
+                """
+                SELECT payload_json
+                FROM events
+                WHERE issue_key = ?
+                  AND state <> 'skipped'
+                ORDER BY received_at DESC
+                """,
+                (issue_key,),
+            ).fetchall()
+        for row in rows:
+            payload = json.loads(row["payload_json"])
+            directive = payload.get("_robomp_directive")
+            if isinstance(directive, dict) and directive.get("authorizes_impl") is True:
+                return True
+        return False
+
     def requeue_event(
         self,
         delivery_id: str,