feat: remember window size (#404)

Fixes #398

lib/core/utils/window_size_listener.dart

@@ -0,0 +1,88 @@
+import 'package:fl_lib/fl_lib.dart';
+import 'package:server_box/data/res/store.dart';
+import 'package:window_manager/window_manager.dart';
+
+abstract final class WindowSizeListener {
+  static final _WindowSizeListener instance = _WindowSizeListener();
+}
+
+final class _WindowSizeListener implements WindowListener {
+  @override
+  void onWindowBlur() {
+  }
+
+  @override
+  void onWindowClose() {
+  }
+
+  @override
+  void onWindowDocked() {
+  }
+
+  @override
+  void onWindowEnterFullScreen() {
+  }
+
+  @override
+  void onWindowEvent(String eventName) {
+  }
+
+  @override
+  void onWindowFocus() {
+  }
+
+  @override
+  void onWindowLeaveFullScreen() {
+  }
+
+  @override
+  void onWindowMaximize() {
+  }
+
+  @override
+  void onWindowMinimize() {
+  }
+
+  @override
+  void onWindowMove() {
+  }
+
+  @override
+  void onWindowMoved() {
+  }
+
+  @override
+  void onWindowResize() {
+    if (!isLinux) return;
+    final current = Stores.setting.windowSize.fetch();
+    if (current.isEmpty) return;
+
+    windowManager.getSize().then((size) {
+      Stores.setting.windowSize.put(size.toIntStr());
+    });
+  }
+
+  @override
+  void onWindowResized() {
+    if (!isMacOS || !isWindows) return;
+    final current = Stores.setting.windowSize.fetch();
+    if (current.isEmpty) return;
+
+    windowManager.getSize().then((size) {
+      Stores.setting.windowSize.put(size.toIntStr());
+    });
+  }
+
+  @override
+  void onWindowRestore() {
+  }
+
+  @override
+  void onWindowUndocked() {
+  }
+
+  @override
+  void onWindowUnmaximize() {
+  }
+
+}