fix(cursor): use stdio ignore, sequential polling, move CursorConfig to types

- Change spawn stdio from piped to 'ignore' preventing buffer deadlock
- Replace setInterval with sequential setTimeout polling
- Fix TOCTOU in SIGKILL escalation (send directly without probing)
- Move CursorConfig interface to types.ts
- Change detectProvider default from 'openai' to 'unknown'
- Remove redundant removePidFile() when PID is null

src/cursor/cursor-daemon.ts

@@ -9,15 +9,9 @@ import { spawn, ChildProcess } from 'child_process';
 import * as fs from 'fs';
 import * as path from 'path';
 import * as http from 'http';
-import type { CursorDaemonStatus } from './types';
+import type { CursorConfig, CursorDaemonStatus } from './types';
 import { getCcsDir } from '../utils/config-manager';
 
-// Temporary interface until #521 adds cursor to unified config
-interface CursorConfig {
-  port: number;
-  model: string;
-}
-
 /**
  * Get Cursor directory path.
  */
@@ -155,11 +149,11 @@ export async function startDaemon(
     const safeResolve = (result: { success: boolean; pid?: number; error?: string }) => {
       if (resolved) return;
       resolved = true;
-      if (checkInterval) clearInterval(checkInterval);
+      if (checkTimeout) clearTimeout(checkTimeout);
       resolve(result);
     };
 
-    let checkInterval: NodeJS.Timeout | null = null;
+    let checkTimeout: NodeJS.Timeout | null = null;
 
     try {
       // Spawn a placeholder Node.js process
@@ -185,9 +179,8 @@ export async function startDaemon(
       ];
 
       proc = spawn(process.execPath, args, {
-        stdio: ['ignore', 'pipe', 'pipe'],
+        stdio: 'ignore',
         detached: true,
-        shell: process.platform === 'win32',
       });
 
       // Unref so parent can exit
@@ -200,7 +193,7 @@ export async function startDaemon(
       // Wait for daemon to be ready (poll for up to 30 seconds)
       let attempts = 0;
       const maxAttempts = 30;
-      checkInterval = setInterval(async () => {
+      const pollHealth = async () => {
         attempts++;
 
         if (await isDaemonRunning(config.port)) {
@@ -218,8 +211,11 @@ export async function startDaemon(
             success: false,
             error: 'Daemon did not start within 30 seconds',
           });
+        } else {
+          checkTimeout = setTimeout(pollHealth, 1000);
         }
-      }, 1000);
+      };
+      checkTimeout = setTimeout(pollHealth, 1000);
 
       proc.on('error', (err) => {
         safeResolve({
@@ -263,7 +259,6 @@ export async function stopDaemon(): Promise<{ success: boolean; error?: string }
 
   if (!pid) {
     // No PID file — daemon is not running or was already stopped
-    removePidFile();
     return { success: true };
   }
 
@@ -287,8 +282,7 @@ export async function stopDaemon(): Promise<{ success: boolean; error?: string }
 
     // Escalate to SIGKILL if process still alive after SIGTERM attempts
     try {
-      process.kill(pid, 0); // Check if still alive
+      process.kill(pid, 'SIGKILL');
-      process.kill(pid, 'SIGKILL'); // Escalate to force kill
     } catch {
       // Already dead — good
     }

src/cursor/cursor-models.ts

@@ -163,7 +163,7 @@ export function detectProvider(modelId: string): string {
   if (modelId.includes('gpt') || /^o\d/.test(modelId)) return 'openai';
   if (modelId.includes('gemini')) return 'google';
   if (modelId.includes('cursor')) return 'cursor';
-  return 'openai';
+  return 'unknown';
 }
 
 /**

src/cursor/types.ts

@@ -4,6 +4,15 @@
  * TypeScript interfaces for the Cursor module.
  */
 
+/**
+ * Cursor daemon configuration.
+ * Temporary interface until #521 adds cursor to unified config.
+ */
+export interface CursorConfig {
+  port: number;
+  model: string;
+}
+
 /**
  * Cursor authentication credentials
  */

tests/unit/cursor/cursor-models.test.ts

@@ -72,8 +72,8 @@ describe('detectProvider', () => {
     expect(detectProvider('cursor-small')).toBe('cursor');
   });
 
-  it('defaults to openai for unknown models', () => {
+  it('defaults to unknown for unrecognized models', () => {
-    expect(detectProvider('unknown-model')).toBe('openai');
+    expect(detectProvider('unknown-model')).toBe('unknown');
   });
 });