Initial commit: HUDini — classic volume HUD for macOS

Menu bar utility that shows a centered HUD overlay with volume bars
when system volume changes. CoreAudio monitoring, auto-fade, works
on all spaces and fullscreen.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Package.swift

@@ -0,0 +1,19 @@
+// swift-tools-version:5.9
+import PackageDescription
+
+let package = Package(
+    name: "HUDini",
+    platforms: [.macOS(.v13)],
+    targets: [
+        .executableTarget(
+            name: "HUDini",
+            path: "Sources/HUDini",
+            exclude: ["Resources"],
+            linkerSettings: [
+                .linkedFramework("Cocoa"),
+                .linkedFramework("CoreAudio"),
+                .linkedFramework("AudioToolbox"),
+            ]
+        )
+    ]
+)