feat: multiplexer queries coordinator for close decisions

src/multiplexer/session-manager.ts

@@ -16,6 +16,8 @@ import { log } from '../utils/logger';
 interface BackgroundJobReader {
   getState(sessionId: string): BackgroundJobState | undefined;
   isRunning(sessionId: string): boolean;
+  deferIfRunning(sessionId: string): boolean;
+  clearDeferredClose(sessionId: string): void;
 }
 
 interface TrackedSession {
@@ -38,7 +40,6 @@ interface SharedSessionState {
   knownSessions: Map<string, KnownSession>;
   spawningSessions: Set<string>;
   closingSessions: Map<string, Promise<void>>;
-  deferredIdleCloses: Set<string>;
 }
 
 interface SessionEvent {
@@ -71,7 +72,6 @@ function getSharedState(): SharedSessionState {
     knownSessions: new Map(),
     spawningSessions: new Set(),
     closingSessions: new Map(),
-    deferredIdleCloses: new Set(),
   };
 
   return globalWithState[SHARED_STATE_KEY];
@@ -83,7 +83,6 @@ export function resetMultiplexerSessionManagerState(): void {
   state.knownSessions.clear();
   state.spawningSessions.clear();
   state.closingSessions.clear();
-  state.deferredIdleCloses.clear();
 }
 
 /**
@@ -101,7 +100,6 @@ export class MultiplexerSessionManager {
   private knownSessions: SharedSessionState['knownSessions'];
   private spawningSessions: SharedSessionState['spawningSessions'];
   private closingSessions: SharedSessionState['closingSessions'];
-  private deferredIdleCloses: SharedSessionState['deferredIdleCloses'];
   private pollInterval?: ReturnType<typeof setInterval>;
   private enabled = false;
 
@@ -115,7 +113,6 @@ export class MultiplexerSessionManager {
     this.knownSessions = sharedState.knownSessions;
     this.spawningSessions = sharedState.spawningSessions;
     this.closingSessions = sharedState.closingSessions;
-    this.deferredIdleCloses = sharedState.deferredIdleCloses;
 
     this.directory = ctx.directory;
     const defaultPort = process.env.OPENCODE_PORT ?? '4096';
@@ -290,7 +287,7 @@ export class MultiplexerSessionManager {
 
     if (statusType) {
       if (statusType !== 'busy') {
-        this.deferredIdleCloses.delete(sessionId);
+        this.backgroundJobBoard?.clearDeferredClose(sessionId);
         return;
       }
 
@@ -322,7 +319,7 @@ export class MultiplexerSessionManager {
       backgroundJobState: this.backgroundJobState(sessionId),
     });
 
-    this.deferredIdleCloses.delete(sessionId);
+    this.backgroundJobBoard?.clearDeferredClose(sessionId);
     await this.closeSession(sessionId, 'deleted');
   }
 
@@ -374,7 +371,7 @@ export class MultiplexerSessionManager {
         if (!status) continue;
 
         if (status.type !== 'idle') {
-          this.deferredIdleCloses.delete(sessionId);
+          this.backgroundJobBoard?.clearDeferredClose(sessionId);
           continue;
         }
 
@@ -419,7 +416,7 @@ export class MultiplexerSessionManager {
   ): Promise<void> {
     if (reason === 'deleted') {
       this.knownSessions.delete(sessionId);
-      this.deferredIdleCloses.delete(sessionId);
+      this.backgroundJobBoard?.clearDeferredClose(sessionId);
     }
 
     const existingClose = this.closingSessions.get(sessionId);
@@ -457,8 +454,7 @@ export class MultiplexerSessionManager {
       });
     }
 
-    if (reason === 'idle' && this.isRunningBackgroundJob(sessionId)) {
-      this.deferredIdleCloses.add(sessionId);
+    if (reason === 'idle' && !this.shouldCloseNow(sessionId)) {
       log(
         '[multiplexer-session-manager] close skipped; background job running',
         {
@@ -472,7 +468,6 @@ export class MultiplexerSessionManager {
       return;
     }
 
-    this.deferredIdleCloses.delete(sessionId);
     this.sessions.delete(sessionId);
 
     log('[multiplexer-session-manager] closing session pane', {
@@ -586,7 +581,7 @@ export class MultiplexerSessionManager {
         directory: known.directory,
         ownerInstanceId: this.instanceId,
       });
-      this.deferredIdleCloses.delete(sessionId);
+      this.backgroundJobBoard?.clearDeferredClose(sessionId);
 
       log('[multiplexer-session-manager] pane respawned on busy', {
         instanceId: this.instanceId,
@@ -622,14 +617,8 @@ export class MultiplexerSessionManager {
     return this.backgroundJobBoard?.getState(sessionId);
   }
 
-  private isRunningBackgroundJob(sessionId: string): boolean {
-    return this.backgroundJobBoard?.isRunning(sessionId) ?? false; // ponytail: intent-revealing query
-  }
-
-  async retryDeferredIdleClose(sessionId: string): Promise<void> {
-    if (!this.enabled) return;
-    if (!this.deferredIdleCloses.has(sessionId)) return;
-    await this.closeSession(sessionId, 'idle');
+  private shouldCloseNow(sessionId: string): boolean {
+    return this.backgroundJobBoard?.deferIfRunning(sessionId) ?? true;
   }
 
   async cleanup(): Promise<void> {
@@ -659,7 +648,8 @@ export class MultiplexerSessionManager {
     this.knownSessions.clear();
     this.spawningSessions.clear();
     this.closingSessions.clear();
-    this.deferredIdleCloses.clear();
+    // ponytail: deferred state lives in coordinator, not here
+    // Note: coordinator has same lifetime as plugin, so no explicit cleanup needed
 
     log('[multiplexer-session-manager] cleanup complete');
   }