feat(client): 字体改本地打包(拉丁全量 + Noto Sans SC GB2312 子集)

生产 PangolinFonts.useBundled=true,离线可用,不再运行时拉 google_fonts;
中文经 fontFamilyFallback=[Noto Sans SC] 兜底,子集外字符再兜系统 CJK 字体。
- 拉丁:Sora/Manrope/JetBrains Mono 静态权重(复用 test/fonts)。
- 中文:Noto Sans SC 变量字体 instance 到 Regular + subset 到 GB2312 6763 字
  (单权重,粗体引擎合成),client/fonts 合计约 3.4MB。
- tools/fonts/make-cjk-subset.sh 可复现生成(GB2312 字表无需联网)。
- 新增 test/unit/fonts_test.dart 锁定接线;golden 因 notdef 占位字形微调已更新。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/pangolin_theme.dart

@@ -154,12 +154,14 @@ class PangolinFonts {
   static const cjk = 'Noto Sans SC';
   static const mono = 'JetBrains Mono';
 
-  /// 测试钩子：true 时用 bundled family（test/fonts/ 经 FontLoader 注册），不走 google_fonts。
-  static bool useBundled = false;
+  /// 生产默认 true：用本地打包 ttf（pubspec fonts: 段），离线可用，不走 google_fonts
+  /// 运行时拉取。测试态由 flutter_test_config.dart 经 FontLoader 注册 test/fonts/。
+  /// 中文经 [cjk]（Noto Sans SC 子集）走 fontFamilyFallback；子集外字符再兜系统 CJK 字体。
+  static bool useBundled = true;
 
   static TextStyle sora({double? fontSize, FontWeight? fontWeight, double? height, double? letterSpacing}) =>
       useBundled
-          ? TextStyle(fontFamily: display, fontSize: fontSize, fontWeight: fontWeight, height: height, letterSpacing: letterSpacing)
+          ? TextStyle(fontFamily: display, fontFamilyFallback: const [cjk], fontSize: fontSize, fontWeight: fontWeight, height: height, letterSpacing: letterSpacing)
           : GoogleFonts.sora(fontSize: fontSize, fontWeight: fontWeight, height: height, letterSpacing: letterSpacing);
 
   static TextStyle manrope(
@@ -167,6 +169,7 @@ class PangolinFonts {
       useBundled
           ? TextStyle(
               fontFamily: sans,
+              fontFamilyFallback: const [cjk],
               fontSize: fontSize,
               fontWeight: fontWeight,
               height: height,
@@ -177,11 +180,11 @@ class PangolinFonts {
 
   static TextStyle jetBrainsMono({double? fontSize, FontWeight? fontWeight, List<FontFeature>? fontFeatures}) =>
       useBundled
-          ? TextStyle(fontFamily: mono, fontSize: fontSize, fontWeight: fontWeight, fontFeatures: fontFeatures)
+          ? TextStyle(fontFamily: mono, fontFamilyFallback: const [cjk], fontSize: fontSize, fontWeight: fontWeight, fontFeatures: fontFeatures)
           : GoogleFonts.jetBrainsMono(fontSize: fontSize, fontWeight: fontWeight, fontFeatures: fontFeatures);
 
   static TextTheme manropeTextTheme(TextTheme base) =>
-      useBundled ? base.apply(fontFamily: sans) : GoogleFonts.manropeTextTheme(base);
+      useBundled ? base.apply(fontFamily: sans, fontFamilyFallback: const [cjk]) : GoogleFonts.manropeTextTheme(base);
 }
 
 /// ── Type scale ──────────────────────────────────────────────────────

client/pubspec.yaml

@@ -46,5 +46,30 @@ flutter:
     - assets/app-icon.svg
     - assets/tray_icon.png
 
-  # ── 字体(由 google_fonts 运行时加载,无需本地 ttf)──
-  # 若需离线/打包字体,下载 ttf 放 fonts/,并按 pubspec 模板恢复 fonts: 段。
+  # ── 字体(本地打包,全平台离线)──
+  # 拉丁全量(Sora/Manrope/JetBrains Mono)+ Noto Sans SC 子集(GB2312 6763 字,单 Regular
+  # 权重;CJK 粗体由引擎合成)。子集由 tools/fonts/make-cjk-subset.sh 可复现生成。
+  # 生产经 PangolinFonts.useBundled=true 走这些 family;中文经 fontFamilyFallback 兜底。
+  fonts:
+    - family: Sora
+      fonts:
+        - asset: fonts/Sora-Regular.ttf
+        - asset: fonts/Sora-SemiBold.ttf
+          weight: 600
+        - asset: fonts/Sora-Bold.ttf
+          weight: 700
+    - family: Manrope
+      fonts:
+        - asset: fonts/Manrope-Regular.ttf
+        - asset: fonts/Manrope-Medium.ttf
+          weight: 500
+        - asset: fonts/Manrope-SemiBold.ttf
+          weight: 600
+        - asset: fonts/Manrope-Bold.ttf
+          weight: 700
+    - family: JetBrains Mono
+      fonts:
+        - asset: fonts/JetBrainsMono-Regular.ttf
+    - family: Noto Sans SC
+      fonts:
+        - asset: fonts/NotoSansSC-Regular-subset.otf

client/test/unit/fonts_test.dart

@@ -0,0 +1,54 @@
+// fonts_test.dart — 本地打包字体接线回归。
+//
+// 锁定 Task 3 的字体改造:生产走 bundled family（非 google_fonts 运行时拉取），
+// 且每个字体函数都把中文兜到 Noto Sans SC（fontFamilyFallback: [cjk]）。
+// flutter_test_config.dart 在测试启动已置 PangolinFonts.useBundled = true。
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pangolin_vpn/pangolin_theme.dart';
+
+void main() {
+  group('PangolinFonts 本地打包接线', () {
+    test('测试态(useBundled=true)由 flutter_test_config 设置', () {
+      // 该 hook 由 test/flutter_test_config.dart 在所有测试前置 true；
+      // 生产代码默认值也是 true（见 pangolin_theme.dart）。
+      expect(PangolinFonts.useBundled, isTrue);
+    });
+
+    test('cjk family 为 Noto Sans SC（与 pubspec fonts: 段一致）', () {
+      expect(PangolinFonts.cjk, 'Noto Sans SC');
+    });
+
+    test('sora() 用 bundled display family 且中文兜底到 cjk', () {
+      final s = PangolinFonts.sora(fontSize: 16);
+      expect(s.fontFamily, PangolinFonts.display);
+      expect(s.fontFamilyFallback, contains(PangolinFonts.cjk));
+    });
+
+    test('manrope() 用 bundled sans family 且中文兜底到 cjk', () {
+      final s = PangolinFonts.manrope(fontSize: 16);
+      expect(s.fontFamily, PangolinFonts.sans);
+      expect(s.fontFamilyFallback, contains(PangolinFonts.cjk));
+    });
+
+    test('jetBrainsMono() 用 bundled mono family 且中文兜底到 cjk', () {
+      final s = PangolinFonts.jetBrainsMono(fontSize: 14);
+      expect(s.fontFamily, PangolinFonts.mono);
+      expect(s.fontFamilyFallback, contains(PangolinFonts.cjk));
+    });
+
+    test('manropeTextTheme 应用 sans family 且中文兜底到 cjk', () {
+      const base = TextTheme(bodyMedium: TextStyle(fontSize: 16));
+      final t = PangolinFonts.manropeTextTheme(base);
+      expect(t.bodyMedium?.fontFamily, PangolinFonts.sans);
+      expect(t.bodyMedium?.fontFamilyFallback, contains(PangolinFonts.cjk));
+    });
+
+    test('PangolinText 标度经由 bundled 接线（中文兜底存在）', () {
+      // 抽查几个常用标度，确保未绕过 PangolinFonts 封装。
+      expect(PangolinText.h1.fontFamilyFallback, contains(PangolinFonts.cjk));
+      expect(PangolinText.body.fontFamilyFallback, contains(PangolinFonts.cjk));
+      expect(PangolinText.mono.fontFamilyFallback, contains(PangolinFonts.cjk));
+    });
+  });
+}