i18n: complete internationalization for v3.8+ features

- Add health status translations (operational, degraded, failed, circuitOpen)
- Add proxy panel translations (serviceAddress, stats, stopped state)
- Add usage filter translations (appType, statusCode, searchPlaceholder)
- Add providerIcon click hints (clickToChange, clickToSelect)
- Add config load error translations for main.tsx
- Complete Japanese proxy section (failoverQueue, autoFailover)
- Fix date/time locale in usage charts and tables
- Use t() function in all hardcoded UI strings

src/components/providers/forms/BasicFormFields.tsx

@@ -52,7 +52,15 @@ export function BasicFormFields({ form }: BasicFormFieldsProps) {
             <button
               type="button"
               className="w-20 h-20 p-3 rounded-xl border-2 border-muted hover:border-primary transition-colors cursor-pointer bg-muted/30 hover:bg-muted/50 flex items-center justify-center"
-              title={currentIcon ? "点击更换图标" : "点击选择图标"}
+              title={
+                currentIcon
+                  ? t("providerIcon.clickToChange", {
+                      defaultValue: "点击更换图标",
+                    })
+                  : t("providerIcon.clickToSelect", {
+                      defaultValue: "点击选择图标",
+                    })
+              }
             >
               <ProviderIcon
                 icon={currentIcon}
@@ -145,7 +153,7 @@ export function BasicFormFields({ form }: BasicFormFieldsProps) {
           <FormItem>
             <FormLabel>{t("provider.websiteUrl")}</FormLabel>
             <FormControl>
-              <Input {...field} placeholder="https://" />
+              <Input {...field} placeholder={t("providerForm.websiteUrlPlaceholder")} />
             </FormControl>
             <FormMessage />
           </FormItem>