fix(security): track executable modification date for primer detection

Includes the executable's modification date in the version hash to ensure ad-hoc and local recompilations correctly trigger the keychain primer UI, preventing unexpected system prompts on boot.

test.swift

@@ -0,0 +1,7 @@
+import Foundation
+print(Bundle.main.infoDictionary ?? "No Info.plist")
+let execPath = Bundle.main.executablePath
+print("Exec path: \(execPath ?? "nil")")
+if let path = execPath, let attr = try? FileManager.default.attributesOfItem(atPath: path), let modDate = attr[.modificationDate] as? Date {
+    print("Mod date: \(modDate)")
+}