test: spawn timeouts on absorbed-PR tests (v1.77 sync-spawn tripwire)

The absorbed community tests (#2748, #2676, #2714, #2720) were authored
before the v1.77 tripwire required a timeout on every sync spawn in the test
trees.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

test/gstack-config-cross-project.test.ts

@@ -19,6 +19,7 @@ let stateRoot: string;
 
 function cfg(args: string[]): { code: number; out: string; err: string } {
   const r = spawnSync(CONFIG, args, {
+    timeout: 30_000,
     encoding: "utf8",
     env: { ...process.env, GSTACK_STATE_ROOT: stateRoot },
   });

test/gstack-skill-start.test.ts

@@ -342,6 +342,7 @@ describe('gstack-skill-start behavior', () => {
 
       fs.writeFileSync(path.join(freshGh, '.feature-prompted-model-overlay'), '');
       const acknowledged = execFileSync(localStart, ['--skill', 'testskill'], {
+        timeout: 30_000,
         encoding: 'utf-8',
         cwd: projectRoot,
         env,

test/hostile-path-writers.test.ts

@@ -35,6 +35,7 @@ function runBin(bin: string, args: string[], env: Record<string, string> = {}) {
   // cannot exec a shebang script directly (spawn would fail before the code
   // under test ever ran).
   const r = spawnSync('bash', [path.join(HOSTILE, 'bin', bin), ...args], {
+    timeout: 30_000,
     encoding: 'utf-8',
     env: { ...process.env, GSTACK_HOME: STATE, GSTACK_STATE_ROOT: '', ...env },
     shell: false,

test/skill-browse-state-extraction.test.ts

@@ -49,7 +49,7 @@ function extractViaSkill(source: string, field: 'pid' | 'port', stateFile: strin
   // have to be reproduced here.
   const pipeline = line!.slice(line!.indexOf('grep -o'));
   const script = `cat ${JSON.stringify(stateFile)} | ${pipeline.replace(/\)$/, '')}`;
-  return execFileSync('bash', ['-c', script], { encoding: 'utf-8' }).trim();
+  return execFileSync('bash', ['-c', script], { encoding: 'utf-8', timeout: 30_000 }).trim();
 }
 
 describe('/open-gstack-browser state-file extraction', () => {