refine(usage): enhance query robustness and error handling

Backend improvements:
- Add InvalidHttpMethod error enum for better error semantics
- Clamp HTTP timeout to 2-30s to prevent config abuse
- Strict HTTP method validation instead of silent fallback to GET

Frontend improvements:
- Add i18n support for usage query errors (en/zh)
- Improve error handling with type-safe unknown instead of any
- Optimize i18n import (direct import instead of dynamic)
- Disable auto-retry for usage queries to avoid API stampede

Additional changes:
- Apply prettier formatting to affected files

Files changed:
- src-tauri/src/error.rs (+2)
- src-tauri/src/usage_script.rs (+8 -2)
- src/i18n/locales/{en,zh}.json (+4 -1 each)
- src/lib/api/usage.ts (+21 -4)
- src/lib/query/queries.ts (+1)
- style: prettier formatting on 6 other files

src-tauri/src/error.rs

@@ -46,6 +46,8 @@ pub enum AppError {
     McpValidation(String),
     #[error("{0}")]
     Message(String),
+    #[error("不支持的 HTTP 方法: {0}")]
+    InvalidHttpMethod(String),
     #[error("{zh} ({en})")]
     Localized {
         key: &'static str,