macOS: Focus Terminal App Intent (#8961)

Closes #8791 
Discussion: #8657 

### Summary
This adds the FocusTerminalIntent App Intent and related function
(focusSurface), allows external tools (such as Shortcuts/Siri) to
programmatically move focus to a specific terminal window or tab.

### Verification
This functionality has been tested across following scenarios,
confirming correct focus behavior for:

- Split Window
- Tab Group
- Quick Terminal

### Note
It is not supported to move focus to a split that is hidden by a zoomed
split. The same applies to the CloseTerminalIntent.

### AI Disclosure
This pull request was made with assistance from Claude Code.
I reviewed all AI-generated code and wrote the final output manually.

macos/Ghostty.xcodeproj/project.pbxproj

@@ -75,6 +75,7 @@
 				"Features/App Intents/CommandPaletteIntent.swift",
 				"Features/App Intents/Entities/CommandEntity.swift",
 				"Features/App Intents/Entities/TerminalEntity.swift",
+				"Features/App Intents/FocusTerminalIntent.swift",
 				"Features/App Intents/GetTerminalDetailsIntent.swift",
 				"Features/App Intents/GhosttyIntentError.swift",
 				"Features/App Intents/InputIntent.swift",

macos/Sources/Features/App Intents/FocusTerminalIntent.swift

@@ -0,0 +1,35 @@
+import AppKit
+import AppIntents
+import GhosttyKit
+
+struct FocusTerminalIntent: AppIntent {
+    static var title: LocalizedStringResource = "Focus Terminal"
+    static var description = IntentDescription("Move focus to an existing terminal.")
+
+    @Parameter(
+        title: "Terminal",
+        description: "The terminal to focus.",
+    )
+    var terminal: TerminalEntity
+
+    @available(macOS 26.0, *)
+    static var supportedModes: IntentModes = .background
+
+    @MainActor
+    func perform() async throws -> some IntentResult {
+        guard await requestIntentPermission() else {
+            throw GhosttyIntentError.permissionDenied
+        }
+
+        guard let surfaceView = terminal.surfaceView else {
+            throw GhosttyIntentError.surfaceNotFound
+        }
+
+        guard let controller = surfaceView.window?.windowController as? BaseTerminalController else {
+            return .result()
+        }
+
+        controller.focusSurface(surfaceView)
+        return .result()
+    }
+}

macos/Sources/Features/QuickTerminal/QuickTerminalController.swift

@@ -247,6 +247,22 @@ class QuickTerminalController: BaseTerminalController {
 
     // MARK: Base Controller Overrides
 
+    override func focusSurface(_ view: Ghostty.SurfaceView) {
+        if visible {
+            // If we're visible, we just focus the surface as normal.
+            super.focusSurface(view)
+            return
+        }
+        // Check if target surface belongs to this quick terminal
+        guard surfaceTree.contains(view) else { return }
+        // Set the target surface as focused
+        DispatchQueue.main.async {
+            Ghostty.moveFocus(to: view)
+        }
+        // Animation completion handler will handle window/app activation
+        animateIn()
+    }
+
     override func surfaceTreeDidChange(from: SplitTree<Ghostty.SurfaceView>, to: SplitTree<Ghostty.SurfaceView>) {
         super.surfaceTreeDidChange(from: from, to: to)
 

macos/Sources/Features/Terminal/BaseTerminalController.swift

@@ -233,6 +233,21 @@ class BaseTerminalController: NSWindowController,
         return newView
     }
 
+    /// Move focus to a surface view.
+    func focusSurface(_ view: Ghostty.SurfaceView) {
+        // Check if target surface is in our tree
+        guard surfaceTree.contains(view) else { return }
+
+        // Move focus to the target surface and activate the window/app
+        DispatchQueue.main.async {
+            Ghostty.moveFocus(to: view)
+            view.window?.makeKeyAndOrderFront(nil)
+            if !NSApp.isActive {
+                NSApp.activate(ignoringOtherApps: true)
+            }
+        }
+    }
+
     /// Called when the surfaceTree variable changed.
     ///
     /// Subclasses should call super first.