feat: add course bar length setting and clear blue glass Dock

mobile/lib/features/profile/settings_page.dart

@@ -17,6 +17,8 @@ class SettingsPage extends StatefulWidget {
 class _SettingsPageState extends State<SettingsPage> {
   late TextEditingController _weeks;
   DateTime? _start;
+  double? _courseHeightDraft;
+  bool _savingHeight = false;
   String? _weeksError, _dateError;
   @override
   void initState() {
@@ -100,6 +102,21 @@ class _SettingsPageState extends State<SettingsPage> {
     }
   }
 
+  Future<void> _saveCourseHeight(double value) async {
+    setState(() => _savingHeight = true);
+    await widget.controller.updateSettings(
+      (current) => current.copyWith(courseHeightScale: value),
+    );
+    if (!mounted) return;
+    setState(() {
+      _courseHeightDraft = null;
+      _savingHeight = false;
+    });
+    if (widget.controller.lastError != null) {
+      _notice(widget.controller.lastError!);
+    }
+  }
+
   void _notice(String text) =>
       ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(text)));
   @override
@@ -203,6 +220,68 @@ class _SettingsPageState extends State<SettingsPage> {
               ),
             ),
             const SizedBox(height: 22),
+            _heading('课程条长度'),
+            SurfaceCard(
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Row(
+                    children: [
+                      Expanded(
+                        child: Text(
+                          '${((_courseHeightDraft ?? s.courseHeightScale) * 100).round()}%',
+                          style: const TextStyle(
+                            fontSize: 18,
+                            fontWeight: FontWeight.w700,
+                            color: river,
+                          ),
+                        ),
+                      ),
+                      TextButton(
+                        onPressed: _savingHeight
+                            ? null
+                            : () => _saveCourseHeight(
+                                AppSettings.defaultCourseHeightScale,
+                              ),
+                        child: const Text('恢复默认'),
+                      ),
+                    ],
+                  ),
+                  Slider(
+                    key: const Key('course-height-slider'),
+                    value: _courseHeightDraft ?? s.courseHeightScale,
+                    min: AppSettings.minCourseHeightScale,
+                    max: AppSettings.maxCourseHeightScale,
+                    divisions: 24,
+                    label:
+                        '${((_courseHeightDraft ?? s.courseHeightScale) * 100).round()}%',
+                    semanticFormatterCallback: (value) =>
+                        '${(value * 100).round()}%',
+                    onChanged: _savingHeight
+                        ? null
+                        : (value) => setState(() => _courseHeightDraft = value),
+                    onChangeEnd: _saveCourseHeight,
+                  ),
+                  const Row(
+                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                    children: [
+                      Text('较短', style: TextStyle(fontSize: 11)),
+                      Text('较长', style: TextStyle(fontSize: 11)),
+                    ],
+                  ),
+                  const SizedBox(height: 10),
+                  Text(
+                    '统一调整课程条长度，老师和教室始终完整显示。',
+                    style: TextStyle(
+                      fontSize: 11,
+                      height: 1.6,
+                      color: ink.withValues(alpha: 0.55),
+                    ),
+                  ),
+                ],
+              ),
+            ),
+            const SizedBox(height: 22),
             _heading('课前提醒'),
             SurfaceCard(
               child: Column(