feat: add external terminal support with cross-platform detection (#565)

* feat(platform): add cross-platform openInTerminal utility

Add utility function to open a terminal in a specified directory:
- macOS: Uses Terminal.app via AppleScript
- Windows: Tries Windows Terminal, falls back to cmd
- Linux: Tries common terminal emulators (gnome-terminal,
  konsole, xfce4-terminal, xterm, x-terminal-emulator)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* feat(server): add open-in-terminal endpoint

Add POST /open-in-terminal endpoint to open a system terminal in the
worktree directory using the cross-platform openInTerminal utility.

The endpoint validates that worktreePath is provided and is an
absolute path for security.

Extracted from PR #558.

* feat(ui): add Open in Terminal action to worktree dropdown

Add "Open in Terminal" option to the worktree actions dropdown menu.
This opens the system terminal in the worktree directory.

Changes:
- Add openInTerminal method to http-api-client
- Add Terminal icon and menu item to worktree-actions-dropdown
- Add onOpenInTerminal prop to WorktreeTab component
- Add handleOpenInTerminal handler to use-worktree-actions hook
- Wire up handler in worktree-panel for both mobile and desktop views

Extracted from PR #558.

* fix(ui): open in terminal navigates to Automaker terminal view

Instead of opening the system terminal, the "Open in Terminal" action
now opens Automaker's built-in terminal with the worktree directory:

- Add pendingTerminalCwd state to app store
- Update use-worktree-actions to set pending cwd and navigate to /terminal
- Add effect in terminal-view to create session with pending cwd

This matches the original PR #558 behavior.

* feat(ui): add terminal open mode setting (new tab vs split)

Add a setting to choose how "Open in Terminal" behaves:
- New Tab: Creates a new tab named after the branch (default)
- Split: Adds to current tab as a split view

Changes:
- Add openTerminalMode setting to terminal state ('newTab' | 'split')
- Update terminal-view to respect the setting
- Add UI in Terminal Settings to toggle the behavior
- Rename pendingTerminalCwd to pendingTerminal with branch name

The new tab mode names tabs after the branch for easy identification.
The split mode is useful for comparing terminals side by side.

* feat(ui): display branch name in terminal header with git icon

- Move branch name display from tab name to terminal header
- Show full branch name (no truncation) with GitBranch icon
- Display branch name for both 'new tab' and 'split' modes
- Persist openTerminalMode setting to server and include in import/export
- Update settings dropdown to simplified "New Tab" label

* feat: add external terminal support with cross-platform detection

Add support for opening worktree directories in external terminals
(iTerm2, Warp, Ghostty, System Terminal, etc.) while retaining the
integrated terminal as the default option.

Changes:
- Add terminal detection for macOS, Windows, and Linux
- Add "Open in Terminal" split-button in worktree dropdown
- Add external terminal selection in Settings > Terminal
- Add default open mode setting (new tab vs split)
- Display branch name in terminal panel header
- Support 20+ terminals across platforms

Part of #558, Closes #550

* fix: address PR review comments

- Add nonce parameter to terminal navigation to allow reopening same
  worktree multiple times
- Fix shell path escaping in editor.ts using single-quote wrapper
- Add validatePathParams middleware to open-in-external-terminal route
- Remove redundant validation block from createOpenInExternalTerminalHandler
- Remove unused pendingTerminal state and setPendingTerminal action
- Remove unused getTerminalInfo function from editor.ts

* fix: address PR review security and validation issues

- Add runtime type check for worktreePath in open-in-terminal handler
- Fix Windows Terminal detection using commandExists before spawn
- Fix xterm shell injection by using sh -c with escapeShellArg
- Use loose equality for null/undefined in useEffectiveDefaultTerminal
- Consolidate duplicate imports from open-in-terminal.js

* chore: update package-lock.json

* fix: use response.json() to prevent disposal race condition in E2E test

Replace response.body() with response.json() in open-existing-project.spec.ts
to fix the "Response has been disposed" error. This matches the pattern used
in other test files.

* Revert "fix: use response.json() to prevent disposal race condition in E2E test"

This reverts commit 36bdf8c24a.

* fix: address PR review feedback for terminal feature

- Add explicit validation for worktreePath in createOpenInExternalTerminalHandler
- Add aria-label to refresh button in terminal settings for accessibility
- Only show "no terminals" message when not refreshing
- Reset initialCwdHandledRef on failure to allow retries
- Use z.coerce.number() for nonce URL param to handle string coercion
- Preserve branchName when creating layout for empty tab
- Update getDefaultTerminal return type to allow null result

---------

Co-authored-by: Kacper <kacperlachowiczwp.pl@wp.pl>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

apps/ui/src/hooks/use-settings-sync.ts

@@ -42,6 +42,7 @@ const SETTINGS_FIELDS_TO_SYNC = [
   'fontFamilySans',
   'fontFamilyMono',
   'terminalFontFamily', // Maps to terminalState.fontFamily
+  'openTerminalMode', // Maps to terminalState.openTerminalMode
   'sidebarOpen',
   'chatHistoryOpen',
   'maxConcurrency',
@@ -68,6 +69,7 @@ const SETTINGS_FIELDS_TO_SYNC = [
   'keyboardShortcuts',
   'mcpServers',
   'defaultEditorCommand',
+  'defaultTerminalId',
   'promptCustomization',
   'eventHooks',
   'projects',
@@ -107,6 +109,9 @@ function getSettingsFieldValue(
   if (field === 'terminalFontFamily') {
     return appState.terminalState.fontFamily;
   }
+  if (field === 'openTerminalMode') {
+    return appState.terminalState.openTerminalMode;
+  }
   return appState[field as keyof typeof appState];
 }
 
@@ -134,6 +139,9 @@ function hasSettingsFieldChanged(
   if (field === 'terminalFontFamily') {
     return newState.terminalState.fontFamily !== prevState.terminalState.fontFamily;
   }
+  if (field === 'openTerminalMode') {
+    return newState.terminalState.openTerminalMode !== prevState.terminalState.openTerminalMode;
+  }
   const key = field as keyof typeof newState;
   return newState[key] !== prevState[key];
 }
@@ -618,6 +626,7 @@ export async function refreshSettingsFromServer(): Promise<boolean> {
       },
       mcpServers: serverSettings.mcpServers,
       defaultEditorCommand: serverSettings.defaultEditorCommand ?? null,
+      defaultTerminalId: serverSettings.defaultTerminalId ?? null,
       promptCustomization: serverSettings.promptCustomization ?? {},
       projects: serverSettings.projects,
       trashedProjects: serverSettings.trashedProjects,
@@ -628,11 +637,16 @@ export async function refreshSettingsFromServer(): Promise<boolean> {
       worktreePanelCollapsed: serverSettings.worktreePanelCollapsed ?? false,
       lastProjectDir: serverSettings.lastProjectDir ?? '',
       recentFolders: serverSettings.recentFolders ?? [],
-      // Terminal font (nested in terminalState)
-      ...(serverSettings.terminalFontFamily && {
+      // Terminal settings (nested in terminalState)
+      ...((serverSettings.terminalFontFamily || serverSettings.openTerminalMode) && {
         terminalState: {
           ...currentAppState.terminalState,
-          fontFamily: serverSettings.terminalFontFamily,
+          ...(serverSettings.terminalFontFamily && {
+            fontFamily: serverSettings.terminalFontFamily,
+          }),
+          ...(serverSettings.openTerminalMode && {
+            openTerminalMode: serverSettings.openTerminalMode,
+          }),
         },
       }),
     });