fix(pty): reject writes to inactive sessions

Reject writes unless the session is running and has a process; return false when process.write throws instead of reporting success.

Intentionally change POST /api/sessions/:id/input for inactive PTYs from HTTP 200 to 400. The shared manager also rejects pty_write when a session exits during permission checks in v1 and v2.

Author: dhaern

src/plugin/pty/output-manager.ts

@@ -2,11 +2,12 @@ import type { PTYSession, ReadResult, SearchResult } from './types.ts'
 
 export class OutputManager {
   write(session: PTYSession, data: string): boolean {
+    if (session.status !== 'running' || !session.process) return false
     try {
-      session.process?.write(data)
+      session.process.write(data)
       return true
     } catch {
-      return true // allow write to exited process for tests
+      return false
     }
   }
 

test/integration.test.ts

@@ -114,8 +114,9 @@ describe('Web Server Integration', () => {
         }
       )
 
+      expect(response.status).toBe(400)
       const result = await response.json()
-      expect(result).toHaveProperty('success')
+      expect(result).toEqual({ error: 'Failed to write to session' })
 
       const errorPromise = new Promise((resolve) => {
         managedTestClient.errorCallbacks.push((message) => {