fix(desktop): repair Windows updater and installer flow (#801)

Prevent stale same-version update metadata from surfacing another install prompt, avoid showing a fake desktop version fallback, and configure the Windows NSIS installer to expose install directory selection.

Fixes #801

Tested: bun run verify
Confidence: high
Scope-risk: moderate

adapters/common/__tests__/format.test.ts

@@ -112,6 +112,12 @@ describe('formatToolUse', () => {
     expect(result).toContain('🔧 Bash')
     expect(result).toContain('npm test')
   })
+
+  it('summarizes file tools with a shortened path', () => {
+    const result = formatToolUse('Read', { file_path: '/Users/test/project/src/index.ts' })
+
+    expect(result).toBe('🔧 Read  …/project/src/index.ts')
+  })
 })
 
 describe('formatPermissionRequest', () => {

adapters/common/__tests__/session-store.test.ts

@@ -88,6 +88,25 @@ describe('SessionStore', () => {
     expect(store2.get('anything')).toBeNull()
   })
 
+  it('uses CLAUDE_CONFIG_DIR for the default session store path', () => {
+    const previousConfigDir = process.env.CLAUDE_CONFIG_DIR
+    process.env.CLAUDE_CONFIG_DIR = tmpDir
+    try {
+      const defaultStore = new SessionStore()
+      defaultStore.set('chat-default', 'uuid-default', '/default-project')
+
+      const savedPath = path.join(tmpDir, 'adapter-sessions.json')
+      expect(fs.existsSync(savedPath)).toBe(true)
+      expect(JSON.parse(fs.readFileSync(savedPath, 'utf8'))['chat-default'].sessionId).toBe('uuid-default')
+    } finally {
+      if (previousConfigDir === undefined) {
+        delete process.env.CLAUDE_CONFIG_DIR
+      } else {
+        process.env.CLAUDE_CONFIG_DIR = previousConfigDir
+      }
+    }
+  })
+
   it('lists all entries', () => {
     store.set('chat-1', 'uuid-1', '/a')
     store.set('chat-2', 'uuid-2', '/b')