fix: server-side ACW auto-dispose (Layer 3) — 30s timeout safety net

When Ozonetel sends an ACW event, starts a 30-second timer. If no
/api/ozonetel/dispose call arrives within that window (frontend
crashed, tab closed, page refreshed), auto-disposes with "General
Enquiry" + autoRelease:true. Agent exits ACW automatically.

Timer is cancelled when:
  - Frontend submits disposition normally (cancelAcwTimer in controller)
  - Agent transitions to Ready or Offline
  - Agent logs out

Wiring: OzonetelAgentModule now imports SupervisorModule (forwardRef
for circular dep), controller injects SupervisorService to cancel
the timer on successful dispose.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/supervisor/supervisor.service.ts

@@ -20,11 +20,20 @@ type AgentStateEntry = {
     timestamp: string;
 };
 
+// ACW auto-dispose: if an agent has been in ACW for longer than this
+// without the frontend calling /api/ozonetel/dispose, the server
+// auto-disposes with a default disposition + autoRelease. This is the
+// Layer 3 safety net — covers browser crash, tab close, page refresh
+// where sendBeacon didn't fire, or any other frontend failure.
+const ACW_TIMEOUT_MS = 30_000; // 30 seconds
+const ACW_DEFAULT_DISPOSITION = 'General Enquiry';
+
 @Injectable()
 export class SupervisorService implements OnModuleInit {
     private readonly logger = new Logger(SupervisorService.name);
     private readonly activeCalls = new Map<string, ActiveCall>();
     private readonly agentStates = new Map<string, AgentStateEntry>();
+    private readonly acwTimers = new Map<string, NodeJS.Timeout>();
     readonly agentStateSubject = new Subject<{ agentId: string; state: AgentOzonetelState; timestamp: string }>();
 
     constructor(
@@ -37,6 +46,17 @@ export class SupervisorService implements OnModuleInit {
         this.logger.log('Supervisor service initialized');
     }
 
+    // Called by the dispose endpoint to cancel the ACW timer
+    // (agent submitted disposition before the timeout)
+    cancelAcwTimer(agentId: string) {
+        const timer = this.acwTimers.get(agentId);
+        if (timer) {
+            clearTimeout(timer);
+            this.acwTimers.delete(agentId);
+            this.logger.log(`[ACW-TIMER] Cancelled for ${agentId} (disposition received)`);
+        }
+    }
+
     handleCallEvent(event: any) {
         const action = event.action;
         const ucid = event.ucid ?? event.monitorUCID;
@@ -71,6 +91,46 @@ export class SupervisorService implements OnModuleInit {
             this.agentStates.set(agentId, { state: mapped, timestamp: eventTime });
             this.agentStateSubject.next({ agentId, state: mapped, timestamp: eventTime });
             this.logger.log(`[AGENT-STATE] Emitted: ${agentId} → ${mapped}`);
+
+            // Layer 3: ACW auto-dispose safety net
+            if (mapped === 'acw') {
+                // Find the most recent UCID for this agent
+                const lastCall = Array.from(this.activeCalls.values())
+                    .filter(c => c.agentId === agentId)
+                    .pop();
+                const ucid = lastCall?.ucid;
+
+                this.cancelAcwTimer(agentId); // clear any existing timer
+                const timer = setTimeout(async () => {
+                    // Check if agent is STILL in ACW (they might have disposed by now)
+                    const current = this.agentStates.get(agentId);
+                    if (current?.state !== 'acw') {
+                        this.logger.log(`[ACW-TIMER] ${agentId} no longer in ACW — skipping auto-dispose`);
+                        return;
+                    }
+                    this.logger.warn(`[ACW-TIMER] ${agentId} stuck in ACW for ${ACW_TIMEOUT_MS / 1000}s — auto-disposing${ucid ? ` (UCID ${ucid})` : ''}`);
+                    try {
+                        if (ucid) {
+                            await this.ozonetel.setDisposition({ agentId, ucid, disposition: ACW_DEFAULT_DISPOSITION });
+                        } else {
+                            await this.ozonetel.changeAgentState({ agentId, state: 'Ready' });
+                        }
+                        this.logger.log(`[ACW-TIMER] Auto-dispose successful for ${agentId}`);
+                    } catch (err: any) {
+                        this.logger.error(`[ACW-TIMER] Auto-dispose failed for ${agentId}: ${err.message}`);
+                        // Last resort: try force-ready
+                        try {
+                            await this.ozonetel.changeAgentState({ agentId, state: 'Ready' });
+                        } catch {}
+                    }
+                    this.acwTimers.delete(agentId);
+                }, ACW_TIMEOUT_MS);
+                this.acwTimers.set(agentId, timer);
+                this.logger.log(`[ACW-TIMER] Started ${ACW_TIMEOUT_MS / 1000}s timer for ${agentId}`);
+            } else if (mapped === 'ready' || mapped === 'offline') {
+                // Agent left ACW normally — cancel the timer
+                this.cancelAcwTimer(agentId);
+            }
         }
     }