Reduce ghost emoji flash in title bar (#4804)

Fixes #4799

This PR attempts to reduce the flash caused by the ghost emoji in the
title bar when opening new windows.

## Changes:

- Initialize `SurfaceView.title` with empty string instead of ghost
emoji

- Simplify title computation logic in `TerminalView`

- Adding a 500ms fallback timer for "👻"

	- Canceling timer if title is set

## Current Status:

While these changes reduce the initial ghost emoji flash, there's still
a brief moment where a folder emoji appears alone in the title bar when
opening a new window. This suggests there might be a race condition or
timing issue with how the title is being set and updated.


https://github.com/user-attachments/assets/3688c9f3-1727-4379-b04d-0bd6ac105728

Would appreciate feedback on the remaining flash issue and suggestions
for further improvements.

macos/Sources/Features/Terminal/TerminalView.swift

@@ -10,7 +10,7 @@ protocol TerminalViewDelegate: AnyObject {
 
     /// The title of the terminal should change.
     func titleDidChange(to: String)
-    
+
     /// The URL of the pwd should change.
     func pwdDidChange(to: URL?)
 
@@ -56,15 +56,10 @@ struct TerminalView<ViewModel: TerminalViewModel>: View {
 
     // The title for our window
     private var title: String {
-        var title = "👻"
-
-        if let surfaceTitle = surfaceTitle {
-            if (surfaceTitle.count > 0) {
-                title = surfaceTitle
-            }
+        if let surfaceTitle, !surfaceTitle.isEmpty {
+            return surfaceTitle
         }
-
-        return title
+        return "👻"
     }
 
     // The pwd of the focused surface as a URL
@@ -72,7 +67,7 @@ struct TerminalView<ViewModel: TerminalViewModel>: View {
         guard let surfacePwd, surfacePwd != "" else { return nil }
         return URL(fileURLWithPath: surfacePwd)
     }
-    
+
     var body: some View {
         switch ghostty.readiness {
         case .loading:

macos/Sources/Ghostty/SurfaceView_AppKit.swift

@@ -12,7 +12,14 @@ extension Ghostty {
         // The current title of the surface as defined by the pty. This can be
         // changed with escape codes. This is public because the callbacks go
         // to the app level and it is set from there.
-        @Published private(set) var title: String = "👻"
+        @Published private(set) var title: String = "" {
+            didSet {
+                if !title.isEmpty {
+                    titleFallbackTimer?.invalidate()
+                    titleFallbackTimer = nil
+                }
+            }
+        }
 
         // The current pwd of the surface as defined by the pty. This can be
         // changed with escape codes.
@@ -113,6 +120,9 @@ extension Ghostty {
         // A small delay that is introduced before a title change to avoid flickers
         private var titleChangeTimer: Timer?
 
+        // A timer to fallback to ghost emoji if no title is set within the grace period
+        private var titleFallbackTimer: Timer?
+
         /// Event monitor (see individual events for why)
         private var eventMonitor: Any? = nil
 
@@ -139,6 +149,13 @@ extension Ghostty {
             // can do SOMETHING.
             super.init(frame: NSMakeRect(0, 0, 800, 600))
 
+            // Set a timer to show the ghost emoji after 500ms if no title is set
+            titleFallbackTimer = Timer.scheduledTimer(withTimeInterval: 0.5, repeats: false) { [weak self] _ in
+                if let self = self, self.title.isEmpty {
+                    self.title = "👻"
+                }
+            }
+
             // Before we initialize the surface we want to register our notifications
             // so there is no window where we can't receive them.
             let center = NotificationCenter.default