macos: set env var for app bundle to detect app launch vs CLI

macos/Sources/AppDelegate.swift

@@ -2,7 +2,6 @@ import AppKit
 import OSLog
 import GhosttyKit
 
-@NSApplicationMain
 class AppDelegate: NSObject, ObservableObject, NSApplicationDelegate, GhosttyAppStateDelegate {
     // The application logger. We should probably move this at some point to a dedicated
     // class/struct but for now it lives here! 🤷‍♂️

macos/Sources/main.swift

@@ -0,0 +1,12 @@
+import AppKit
+import Cocoa
+
+// We put the GHOSTTY_MAC_APP env var into the Info.plist to detect
+// whether we launch from the app or not. A user can fake this if
+// they want but they're doing so at their own detriment...
+let process = ProcessInfo.processInfo
+if (process.environment["GHOSTTY_MAC_APP"] == "") {
+    AppDelegate.logger.warning("NOT IN THE MAC APP")
+}
+
+_ = NSApplicationMain(CommandLine.argc, CommandLine.unsafeArgv)