fix(monitoring): restore SQLite token statistics (#2479)

* fix(monitoring): restore SQLite token statistics

Allow the monitored SQLite strftime bucket expression through the tenant SQL guard and preserve structured backend errors in the token dashboard. Add persistence and frontend regressions.\n\nVerified-by: independent-review

* test(runtime): accept reconcile timeout in capacity stub

Keep the PostgreSQL capacity probe aligned with the runtime handler contract and assert the bounded reconcile timeout.

---------

Co-authored-by: dadachann <185672915+dadachann@users.noreply.github.com>

tests/unit_tests/persistence/test_tenant_uow.py

@@ -964,6 +964,7 @@ async def test_scoped_session_rejects_raw_or_unapproved_sql(
             sa.func.date_trunc('hour', sa.column('timestamp')),
             sa.func.length(sa.literal('value')),
             sa.func.nullif(sa.literal('value'), sa.literal('')),
+            sa.func.strftime('%Y-%m-%d %H:00', sa.column('timestamp')),
         ),
         sa.select(sa.column('embedding').op('<=>')(sa.literal([0.1]))),
         sa.select(sa.cast(sa.column('embedding'), Vector(384))),
@@ -977,6 +978,19 @@ async def test_scoped_sql_structure_allows_only_the_production_vocabulary(statem
     _validate_scoped_statement_call((statement,), {})
 
 
+async def test_scoped_session_executes_sqlite_strftime() -> None:
+    engine = create_async_engine('sqlite+aiosqlite:///:memory:')
+    try:
+        async with TenantUnitOfWork(engine, 'workspace-a') as uow:
+            result = await uow.session.execute(
+                sa.select(sa.func.strftime('%Y-%m-%d %H:00', sa.literal('2026-08-28 03:45:00')))
+            )
+
+        assert result.scalar_one() == '2026-08-28 03:00'
+    finally:
+        await engine.dispose()
+
+
 async def test_scoped_sql_rejects_public_execution_options() -> None:
     statement = sa.select(sa.literal(1))
     with pytest.raises(ScopedSessionTransactionError, match='execution options'):