Bug: agents table INSERT/UPDATE fails with InvalidColumnReference on PostgreSQL with logical replication

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### Dify version

1.16.0

### Cloud or Self Hosted

Self Hosted (Docker)

### Steps to reproduce

1. Use PostgreSQL 15+ with logical replication enabled (`wal_level = logical`) and a publication on the `dify` database.
2. Upgrade to Dify 1.16.0 (migrations run correctly).
3. Try to create an Agent app via API or UI → `POST /console/api/agent`.

### ✔️ Expected Behavior

Agent creation succeeds.

### ❌ Actual Behavior

Creating an Agent app fails with `500 Internal Server Error` on PostgreSQL instances where logical replication is enabled.sqlalchemy.exc.ProgrammingError: (psycopg2.errors.InvalidColumnReference) cannot update table "agents"
DETAIL: Replica identity must not contain unpublished generated columns.

[SQL: UPDATE agents SET active_config_snapshot_id=%(active_config_snapshot_id)s::UUID, updated_at=CURRENT_TIMESTAMP WHERE agents.id = %(agents_id)s::UUID]

Start with the POST /console/api/agent code path and the agents table update shown in the SQL error. Reproduce the failure on PostgreSQL 15+ with wal_level=logical and a publication, then trace the relevant schema and migration behavior. Done means Agent creation succeeds under logical replication without InvalidColumnReference and remains covered by a regression test.

Written by the indexing model from the issue text.