i18n: complete internationalization for provider and usage query panels

- Add 45+ new translation keys for usage query and usage script features
- Fix duplicate provider object in translation files that caused missing translations
- Remove all hardcoded Chinese text and defaultValue fallbacks from components
- Add proper translations for:
  * Usage footer (query status, plan usage display)
  * Usage script modal (script editor, validation, test controls)
  * Provider forms (basic fields, endpoints, model selectors)
  * Provider dialogs (add/edit hints and titles)

Modified 16 files:
- 2 translation files (zh.json, en.json)
- 14 component files (removed defaultValue, added t() calls)

All UI text now properly supports Chinese/English switching.

src/components/providers/forms/ClaudeFormFields.tsx

@@ -137,15 +137,11 @@ export function ClaudeFormFields({
       {shouldShowSpeedTest && (
         <EndpointField
           id="baseUrl"
-          label={t("providerForm.apiEndpoint", { defaultValue: "API 端点" })}
+          label={t("providerForm.apiEndpoint")}
           value={baseUrl}
           onChange={onBaseUrlChange}
-          placeholder={t("providerForm.apiEndpointPlaceholder", {
-            defaultValue: "https://api.example.com",
-          })}
-          hint={t("providerForm.apiHint", {
-            defaultValue: "API 端点地址用于连接服务器",
-          })}
+          placeholder={t("providerForm.apiEndpointPlaceholder")}
+          hint={t("providerForm.apiHint")}
           onManageClick={() => onEndpointModalToggle(true)}
         />
       )}