fix: move deep-link permission to platform-specific capability

tauri-plugin-deep-link does not register permissions on Linux
(URLs are passed as CLI args instead). Split deep-link:default
into a separate capability file limited to macOS and Windows.

src-tauri/capabilities/deep-link.json

@@ -0,0 +1,10 @@
+{
+  "$schema": "../gen/schemas/desktop-schema.json",
+  "identifier": "deep-link",
+  "description": "Deep link 权限（仅 macOS 和 Windows）",
+  "windows": ["main"],
+  "platforms": ["macOS", "windows"],
+  "permissions": [
+    "deep-link:default"
+  ]
+}

src-tauri/capabilities/default.json

@@ -38,7 +38,6 @@
     "global-shortcut:allow-register",
     "global-shortcut:allow-unregister",
     "global-shortcut:allow-is-registered",
-    "autostart:default",
-    "deep-link:default"
+    "autostart:default"
   ]
 }