Remove CSV-backed agent jobs (#34413)

## What changed

- Remove the `spawn_agents_on_csv` and `report_agent_job_result` tools and their agent-job runtime and state models.
- Drop the legacy `agent_jobs` and `agent_job_items` tables during state database migration.
- Keep `features.enable_fanout` and `agents.job_max_runtime_seconds` accepted as no-op compatibility settings while omitting them from the generated configuration schema.

## Testing

- Verify upgrades remove both legacy agent-job tables.
- Verify the removed feature and configuration keys still parse without taking effect.

GitOrigin-RevId: 8cc3337da78c67162229f02f40a747f503542646

codex-rs/cli/src/main.rs

@@ -4039,6 +4039,16 @@ mod tests {
         );
     }
 
+    #[test]
+    fn feature_toggles_accept_removed_enable_fanout_flag() {
+        let toggles = FeatureToggles {
+            enable: vec!["enable_fanout".to_string()],
+            disable: Vec::new(),
+        };
+        let overrides = toggles.to_overrides().expect("valid features");
+        assert_eq!(overrides, vec!["features.enable_fanout=true".to_string(),]);
+    }
+
     #[test]
     fn feature_toggles_unknown_feature_errors() {
         let toggles = FeatureToggles {