fix(state): tolerate malformed session marker JSON

hermes_state_gateway.py

@@ -12,14 +12,15 @@ import time
 from pathlib import Path
 from typing import Any, Dict, List, Optional, Set, Tuple
 
-from hermes_state_common import _RECOVERABLE_END_REASONS_SQL, _RESET_END_REASONS_SQL, _sql_session_last_active
+from hermes_state_common import (
+    _RECOVERABLE_END_REASONS_SQL, _RESET_END_REASONS_SQL, _sql_json_extract, _sql_session_last_active)
 
 # Log-record parity with the origin module (caplog tests pin "hermes_state").
 logger = logging.getLogger("hermes_state")
 
 # Recursive CTE naming a session plus its compression ancestors (rows a
 # resume must keep on one routing peer); branch/delegate/tool rows stop it.
-_COMPRESSION_LINEAGE_CTE = """
+_COMPRESSION_LINEAGE_CTE = f"""
                     WITH RECURSIVE compression_lineage(id) AS (
                         SELECT ?
                         UNION
@@ -28,14 +29,8 @@ _COMPRESSION_LINEAGE_CTE = """
                         JOIN sessions child ON child.id = lineage.id
                         JOIN sessions parent ON parent.id = child.parent_session_id
                         WHERE parent.end_reason = 'compression'
-                          AND json_extract(
-                              COALESCE(child.model_config, '{}'),
-                              '$._branched_from'
-                          ) IS NULL
-                          AND json_extract(
-                              COALESCE(child.model_config, '{}'),
-                              '$._delegate_from'
-                          ) IS NULL
+                          AND {_sql_json_extract('child.model_config', '$._branched_from')} IS NULL
+                          AND {_sql_json_extract('child.model_config', '$._delegate_from')} IS NULL
                           AND COALESCE(child.source, '') != 'tool'
                     )
                 """
@@ -108,10 +103,8 @@ _ORPHANS_SQL = f"""
                   AND EXISTS (SELECT 1 FROM messages m
                                WHERE m.session_id = o.id)
                   AND COALESCE(o.source, '') != 'tool'
-                  AND json_extract(COALESCE(o.model_config, '{{}}'),
-                                   '$._branched_from') IS NULL
-                  AND json_extract(COALESCE(o.model_config, '{{}}'),
-                                   '$._delegate_from') IS NULL
+                  AND {_sql_json_extract('o.model_config', '$._branched_from')} IS NULL
+                  AND {_sql_json_extract('o.model_config', '$._delegate_from')} IS NULL
                 ORDER BY o.started_at ASC
                 """
 _ORPHAN_LINEAGE_DONOR_SQL = f"""