fix(test): give each unit test file its own HOME (#927)

Commands resolve ~/.teamai from HOME, so a unit test that reached the real
home shared the sync lock with every teamai session on the machine.
push-env.test.ts failed while another session held ~/.teamai/.sync-lock
(#924). A setup file, listed first so module-level home paths see it too,
now points HOME/USERPROFILE at an empty temp dir per test file. The e2e
config keeps the real home, which CI prepares.

src/__tests__/helpers/isolate-home.ts

@@ -0,0 +1,19 @@
+import fs from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import { afterAll } from 'vitest';
+
+// Commands resolve ~/.teamai (config, state, the sync lock) from HOME at call
+// time. A test that reaches the real home shares that state with every teamai
+// session on the machine, so a live session's lock made push() tests fail
+// (#924). Give each test file, and the CLIs it spawns, its own empty home.
+// A test that stubs HOME itself still wins, and unstubbing restores this one.
+// Long path, like other temp roots (#870): Windows can hand out a short
+// 8.3 tmpdir that paths resolved later would not match.
+const home = fs.realpathSync.native(fs.mkdtempSync(path.join(os.tmpdir(), 'teamai-test-home-')));
+process.env.HOME = home;
+process.env.USERPROFILE = home;
+
+afterAll(() => {
+  fs.rmSync(home, { recursive: true, force: true });
+});

src/__tests__/isolate-home.test.ts

@@ -0,0 +1,17 @@
+import { describe, it, expect } from 'vitest';
+import os from 'node:os';
+import path from 'node:path';
+import { TEAMAI_SOURCES_DIR } from '../types.js';
+import { getUserHome } from '../utils/home.js';
+
+// Guards helpers/isolate-home.ts (#924): a unit test that reaches the real home
+// shares ~/.teamai, and its sync lock, with every teamai session on the machine.
+describe('unit test home isolation', () => {
+  it('runs each test file with a temp home, not the real one', () => {
+    expect(getUserHome()).not.toBe(os.userInfo().homedir);
+  });
+
+  it('isolates the home before any module builds a path from it', () => {
+    expect(TEAMAI_SOURCES_DIR).toBe(path.join(getUserHome(), '.teamai', 'sources'));
+  });
+});

vitest.config.ts

@@ -4,7 +4,12 @@ export default defineConfig({
   test: {
     include: ['src/__tests__/**/*.test.ts'],
     exclude: ['src/__tests__/e2e/**', 'src/__tests__/*-e2e.test.ts'],
-    setupFiles: ['src/__tests__/helpers/clear-agent-session-env.ts'],
+    // isolate-home first: the other setup file imports modules that build
+    // home paths at load time.
+    setupFiles: [
+      'src/__tests__/helpers/isolate-home.ts',
+      'src/__tests__/helpers/clear-agent-session-env.ts',
+    ],
     // CI workers can be resource-constrained under parallel load, which made
     // otherwise-fast tests sporadically exceed vitest's 5s default timeout.
     testTimeout: 15000,