fix: stamp environment on agent_events rows

The agent_events table has an `environment` column and AgentEventsController
filters on it, but the INSERT never populated it — every row got the
column default ('default'). Result: Timeline on the Application Runtime
page was empty whenever the user's selected env was anything other than
'default'.

Thread env through the write path:
- AgentEventRepository.insert + AgentEventService.recordEvent gain an
  `environment` param; delete the no-env query overload (unused).
- ClickHouseAgentEventRepository.insert writes the column (falls back to
  'default' on null to match column DEFAULT).
- All 5 callers source env from the agent registry (AgentInfo.environmentId)
  or the registration request body; AgentLifecycleMonitor, deregister,
  command ack, event ingestion, register/re-register.
- Integration test updated for the new signatures.

Pre-existing rows in deployed CH will still report environment='default'.
New events from this build forward will carry the correct env. Backfill
(UPDATE ... FROM apps) is left as a manual DB step if historical timeline
is needed for non-default envs.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cameleer-server-core/src/main/java/com/cameleer/server/core/agent/AgentEventRepository.java

@@ -5,9 +5,7 @@ import java.util.List;
 
 public interface AgentEventRepository {
 
-    void insert(String instanceId, String applicationId, String eventType, String detail);
-
-    List<AgentEventRecord> query(String applicationId, String instanceId, Instant from, Instant to, int limit);
+    void insert(String instanceId, String applicationId, String environment, String eventType, String detail);
 
     List<AgentEventRecord> query(String applicationId, String instanceId, String environment, Instant from, Instant to, int limit);
 }

cameleer-server-core/src/main/java/com/cameleer/server/core/agent/AgentEventService.java

@@ -16,13 +16,9 @@ public class AgentEventService {
         this.repository = repository;
     }
 
-    public void recordEvent(String instanceId, String applicationId, String eventType, String detail) {
-        log.debug("Recording agent event: instance={}, app={}, type={}", instanceId, applicationId, eventType);
-        repository.insert(instanceId, applicationId, eventType, detail);
-    }
-
-    public List<AgentEventRecord> queryEvents(String applicationId, String instanceId, Instant from, Instant to, int limit) {
-        return repository.query(applicationId, instanceId, from, to, limit);
+    public void recordEvent(String instanceId, String applicationId, String environment, String eventType, String detail) {
+        log.debug("Recording agent event: instance={}, app={}, env={}, type={}", instanceId, applicationId, environment, eventType);
+        repository.insert(instanceId, applicationId, environment, eventType, detail);
     }
 
     public List<AgentEventRecord> queryEvents(String applicationId, String instanceId, String environment, Instant from, Instant to, int limit) {