fix(cli): carry catalog through the picker so BigQuery/Snowflake/SQL Server scope filters match

The setup picker's KtxTableListEntry was a 2-level { schema, name }, so
qualifiedTableId always wrote db.name into enabled_tables. When BigQuery,
Snowflake, or SQL Server later ran fast ingest, their introspect step filtered
the scope set with scopedTableNames(scope, { catalog: projectId|database, db })
— catalog was non-null on the introspect side but null in the scope refs, so
every entry was rejected, the live-database adapter staged zero table files,
and detect() failed with 'Adapter "live-database" did not recognize fetched
source output'.

Align the picker boundary with the canonical 3-level KtxTableRef:

- Add catalog: string | null to KtxTableListEntry.
- BigQuery/Snowflake/SQL Server listTables populate catalog from the
  resolved projectId / database; Postgres/MySQL/ClickHouse/SQLite set null.
- qualifiedTableId emits catalog.schema.name when catalog is non-null
  (resolveEnabledTables already accepts the 3-part shape) and
  schemasFromEnabledTables now goes through parseDottedTableEntry so it
  recovers the schema correctly from both 2-part and 3-part entries.
- Export parseDottedTableEntry from enabled-tables.ts (@internal) for picker
  reuse.

Update listTables expectations in all seven connector tests and the setup /
picker test fixtures. Add a picker regression test that covers the
catalog-bearing round-trip (save + refine).

packages/cli/test/connectors/postgres/connector.test.ts

@@ -390,9 +390,9 @@ describe('KtxPostgresScanConnector', () => {
     await expect(connector.getTableRowCount({ db: 'public', name: 'orders' })).resolves.toBe(3);
     await expect(connector.listSchemas()).resolves.toEqual(['public']);
     await expect(connector.listTables(['public'])).resolves.toEqual([
-      { schema: 'public', name: 'customers', kind: 'table' },
-      { schema: 'public', name: 'orders', kind: 'table' },
-      { schema: 'public', name: 'recent_orders', kind: 'view' },
+      { catalog: null, schema: 'public', name: 'customers', kind: 'table' },
+      { catalog: null, schema: 'public', name: 'orders', kind: 'table' },
+      { catalog: null, schema: 'public', name: 'recent_orders', kind: 'view' },
     ]);
     await expect(connector.testConnection()).resolves.toEqual({ success: true });