fix(state): route the remaining model_config marker reads through _sql_json_extract

Sibling widening of the #101726 salvage: FTS_TRIGRAM_SESSION_SQL (trigram view/triggers/backfill),
the v16 delegate-tagging data migration and reopen_session's legacy reset-child stamp still called
json_extract() on the raw model_config cell, so one malformed JSON row could still abort FTS
maintenance, a schema migration or /resume of a reset child. Zero raw model_config json_extract
reads remain in hermes_state_*.py.

hermes_state_common.py

@@ -763,7 +763,7 @@ FTS_TRIGRAM_EXCLUDED_SOURCES = ("cron", "subagent")
 FTS_TRIGRAM_SESSION_SQL = (
     "source NOT IN ("
     + ", ".join(f"'{src}'" for src in FTS_TRIGRAM_EXCLUDED_SOURCES)
-    + ") AND json_extract(COALESCE(model_config, '{}'), '$._delegate_from') IS NULL"
+    + f") AND {_sql_json_extract('model_config', '$._delegate_from')} IS NULL"
 )
 
 

hermes_state_schema.py

@@ -24,7 +24,7 @@ from hermes_state_common import (
     DEFERRED_INDEX_SQL, FTS_CJK_STALE_KEY, FTS_REBUILD_DEFERRAL_KEY, FTS_STALE_KEY, FTS_SQL,
     FTS_STORAGE_VERSION, FTS_TOOL_FULL_CONTENT_HIGH_WATER_KEY, FTS_TRIGRAM_SQL, LEGACY_FTS_SQL,
     LEGACY_FTS_TRIGRAM_SQL, SCHEMA_SQL,
-    SCHEMA_VERSION, _FTS_CJK_TRIGGERS, _FTS_TRIGGERS, _ephemeral_child_sql, fts_rebuild_admission,
+    SCHEMA_VERSION, _FTS_CJK_TRIGGERS, _FTS_TRIGGERS, _ephemeral_child_sql, _sql_json_extract, fts_rebuild_admission,
 )
 from hermes_state_holders import _read_proc_argv
 
@@ -979,14 +979,14 @@ class SessionSchemaMixin:
                     "UPDATE sessions SET model_config = json_set("
                     "COALESCE(model_config, '{}'), '$._delegate_from', parent_session_id) "
                     f"WHERE parent_session_id IS NOT NULL "
-                    "AND json_extract(COALESCE(model_config, '{}'), '$._delegate_from') IS NULL "
+                    f"AND {_sql_json_extract('model_config', '$._delegate_from')} IS NULL "
                     f"AND {_ephemeral_child_sql('sessions')}"
                 )
                 cursor.execute(
                     "UPDATE sessions SET model_config = json_set("
                     "COALESCE(model_config, '{}'), '$._delegate_from', '__orphaned__') WHERE parent_session_id IS NULL "
-                    "AND json_extract(COALESCE(model_config, '{}'), '$._delegate_from') IS NULL "
-                    "AND json_extract(COALESCE(model_config, '{}'), '$._branched_from') IS NULL "
+                    f"AND {_sql_json_extract('model_config', '$._delegate_from')} IS NULL "
+                    f"AND {_sql_json_extract('model_config', '$._branched_from')} IS NULL "
                     "AND title IS NULL AND message_count <= 25 AND EXISTS (SELECT 1 FROM messages m "
                     "            WHERE m.session_id = sessions.id AND m.role = 'tool') "
                     "AND NOT EXISTS (SELECT 1 FROM sessions ch "

hermes_state_sessions.py

@@ -454,8 +454,7 @@ class SessionSessionsMixin:
             conn.execute(
                 "UPDATE sessions AS child SET model_config = json_set("
                 "COALESCE(child.model_config, '{}'), '$._reset_from', child.parent_session_id) "
-                "WHERE child.parent_session_id = ? AND json_extract(COALESCE(child.model_config, '{}'), "
-                "                 '$._reset_from') IS NULL "
+                f"WHERE child.parent_session_id = ? AND {_sql_json_extract('child.model_config', '$._reset_from')} IS NULL "
                 f"AND {_legacy_reset_child_sql('child', _session_ids_placeholders(_RESET_END_REASONS))}",
                 (session_id, *_RESET_END_REASONS),
             )