feat: 完成智能电网电工端 Flutter 应用初始化

创建完整的 Flutter 项目结构，包含 Android 和 iOS 平台配置、核心网络层、路由、状态管理及业务模块（订单、收益、认证），适配原 uni-app 项目功能逻辑

lib/shared/widgets/app_feedback.dart

@@ -0,0 +1,143 @@
+import 'package:flutter/material.dart';
+
+import '../../core/app_keys.dart';
+import '../../core/theme/app_colors.dart';
+import '../../core/theme/app_dimens.dart';
+import '../../core/theme/app_typography.dart';
+
+/// `uni.showToast({ title, icon })` 的等价实现。
+/// 不依赖调用方的 BuildContext，可在任意异步回调里安全使用。
+void showAppToast(String title, {bool success = false}) {
+  final messenger = AppKeys.scaffoldMessenger.currentState;
+  if (messenger == null) return;
+  messenger
+    ..clearSnackBars()
+    ..showSnackBar(
+      SnackBar(
+        content: Row(
+          children: [
+            if (success) ...[
+              const Icon(
+                Icons.check_circle,
+                size: 18,
+                color: AppColors.success,
+              ),
+              const SizedBox(width: 8),
+            ],
+            Expanded(
+              child: Text(
+                title,
+                style: AppTypography.bodyMd.copyWith(color: AppColors.surface),
+              ),
+            ),
+          ],
+        ),
+        backgroundColor: AppColors.inverseSurface,
+        behavior: SnackBarBehavior.floating,
+        margin: const EdgeInsets.all(AppSpacing.md),
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(AppRadius.lg),
+        ),
+        duration: Duration(milliseconds: success ? 1500 : 2200),
+      ),
+    );
+}
+
+/// `uni.showLoading({ title })` 的等价实现，返回关闭函数。
+VoidCallback showAppLoading([String title = '加载中...']) {
+  final navigator = AppKeys.rootNavigator.currentState;
+  if (navigator == null) return () {};
+  var closed = false;
+  showDialog<void>(
+    context: navigator.context,
+    barrierDismissible: false,
+    builder: (_) => PopScope(
+      canPop: false,
+      child: Center(
+        child: Container(
+          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 20),
+          decoration: BoxDecoration(
+            color: const Color(0xCC000000),
+            borderRadius: BorderRadius.circular(AppRadius.lg),
+          ),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              const SizedBox(
+                width: 26,
+                height: 26,
+                child: CircularProgressIndicator(
+                  strokeWidth: 2.4,
+                  valueColor: AlwaysStoppedAnimation(Colors.white),
+                ),
+              ),
+              const SizedBox(height: 12),
+              Text(
+                title,
+                style: AppTypography.bodyMd.copyWith(color: Colors.white),
+              ),
+            ],
+          ),
+        ),
+      ),
+    ),
+  );
+  return () {
+    if (closed) return;
+    closed = true;
+    final current = AppKeys.rootNavigator.currentState;
+    if (current != null && current.canPop()) current.pop();
+  };
+}
+
+/// `uni.showModal({ title, content })` 的等价实现，返回用户是否点了确认。
+Future<bool> showAppConfirm({
+  required String title,
+  required String content,
+  String confirmText = '确定',
+  String cancelText = '取消',
+  bool destructive = false,
+}) async {
+  final navigator = AppKeys.rootNavigator.currentState;
+  if (navigator == null) return false;
+  final result = await showDialog<bool>(
+    context: navigator.context,
+    builder: (ctx) => AlertDialog(
+      backgroundColor: AppColors.surfaceContainerLowest,
+      surfaceTintColor: Colors.transparent,
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.circular(AppRadius.xl),
+      ),
+      title: Text(
+        title,
+        textAlign: TextAlign.center,
+        style: AppTypography.bodyLg.copyWith(fontWeight: FontWeight.w700),
+      ),
+      content: Text(
+        content,
+        textAlign: TextAlign.center,
+        style: AppTypography.bodyMd.copyWith(color: AppColors.textMuted),
+      ),
+      actionsAlignment: MainAxisAlignment.spaceEvenly,
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.of(ctx).pop(false),
+          child: Text(
+            cancelText,
+            style: AppTypography.bodyLg.copyWith(color: AppColors.textMuted),
+          ),
+        ),
+        TextButton(
+          onPressed: () => Navigator.of(ctx).pop(true),
+          child: Text(
+            confirmText,
+            style: AppTypography.bodyLg.copyWith(
+              color: destructive ? AppColors.tertiaryContainer : AppColors.primary,
+            ),
+          ),
+        ),
+      ],
+    ),
+  );
+  return result ?? false;
+}