feat: 状态栏UI增强 - 状态色 + 订阅精简 + 加载优化 - #19

根据用量百分比动态显示不同颜色：
- 0-50%: 绿色（充足）
- 50-80%: 黄色（注意）
- 80%+: 红色（紧急）

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

将高饱和度的亮色改为更柔和的色调：
- 绿色: #46 → #114 (柔和绿)
- 黄色: #226 → #179 (柔和黄/橙)
- 红色: #196 → #174 (柔和红/粉)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

- 红色: #174 → #167 (更红，不再偏粉)
- 删除三色演示调试代码

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

1. 语义化颜色（固定颜色，不再随机）：
   - PLUS/PRO/MAX: 橙色（高级套餐）
   - PAYGO: 蓝色（按需套餐）
   - FREE: 灰色（免费套餐）

2. 精简显示格式：
   - 旧: PLUS ¥198/月 可重置2次 53天
   - 新: PLUS ¥198/月 53d
   - 减少约40%字符，窄终端友好

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

1. 天数单位 d → 天
2. 排序逻辑：FREE 优先，然后按剩余天数升序

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

已完成并移除：
- 用量段：状态色功能
- 订阅段：精简信息 + 语义化颜色

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

1. API 失败时自动降级使用缓存数据
2. 完全无数据时显示"⏳ 获取中..."
3. API 成功后自动更新缓存

提升用户体验：网络异常时不再显示空白

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>