feat: update dependencies and integrate skin manager

- Added `dartamp_skin` as a local dependency in `pubspec.yaml`.
- Updated `path_provider` to version ^2.1.5.
- Modified `test_driver/app.dart` to initialize `SkinManager` and pass it to `DartampApp`.
- Updated `generated_plugins.cmake` to include `jni` in the FFI plugin list.

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

macos/Runner/AppDelegate.swift

@@ -161,4 +161,8 @@ class AppDelegate: FlutterAppDelegate {
   @IBAction func setUIScale3x(_ sender: NSMenuItem) {
     send("setUIScale", ["scale": 3.0])
   }
+
+  @IBAction func importSkin(_ sender: NSMenuItem) {
+    send("importSkin")
+  }
 }

macos/Runner/Base.lproj/MainMenu.xib

@@ -34,6 +34,12 @@
                             </menuItem>
                             <menuItem isSeparatorItem="YES" id="VOq-y0-SEH"/>
                             <menuItem title="Preferences…" keyEquivalent="," id="BOF-NM-1cW"/>
+                            <menuItem title="Load Skin…" id="mnu-load-skin">
+                                <modifierMask key="keyEquivalentModifierMask"/>
+                                <connections>
+                                    <action selector="importSkin:" target="Voe-Tx-rLC" id="act-import-skin"/>
+                                </connections>
+                            </menuItem>
                             <menuItem isSeparatorItem="YES" id="wFC-TO-SCJ"/>
                             <menuItem title="Services" id="NMo-om-nkz">
                                 <modifierMask key="keyEquivalentModifierMask"/>