feat(macos): add deep link support for qobuzapp:// URLs

Add tauri-plugin-deep-link to handle qobuzapp:// URLs on macOS, where
the OS delivers URLs via Apple Events instead of CLI arguments.

- Register qobuzapp scheme in tauri.conf.json (injected into Info.plist)
- Add on_open_url handler for Apple Event URL delivery
- Extract is_qobuz_link() and handle_qobuz_link() helpers to deduplicate
  URL matching across single-instance, first-launch, and deep-link paths
- Tighten URL matching from contains() to starts_with() for security
- Log emit errors instead of silently discarding them

src-tauri/tauri.conf.json

@@ -31,6 +31,13 @@
       }
     }
   },
+  "plugins": {
+    "deep-link": {
+      "desktop": {
+        "schemes": ["qobuzapp"]
+      }
+    }
+  },
   "bundle": {
     "active": true,
     "targets": "all",