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/hooks/useProxyConfig.ts

@@ -5,6 +5,7 @@
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { invoke } from "@tauri-apps/api/core";
 import { toast } from "sonner";
+import { useTranslation } from "react-i18next";
 import type { ProxyConfig } from "@/types/proxy";
 
 /**
@@ -12,6 +13,7 @@ import type { ProxyConfig } from "@/types/proxy";
  */
 export function useProxyConfig() {
   const queryClient = useQueryClient();
+  const { t } = useTranslation();
 
   // 查询配置
   const { data: config, isLoading } = useQuery({
@@ -24,12 +26,16 @@ export function useProxyConfig() {
     mutationFn: (newConfig: ProxyConfig) =>
       invoke("update_proxy_config", { config: newConfig }),
     onSuccess: () => {
-      toast.success("代理配置已保存", { closeButton: true });
+      toast.success(t("proxy.settings.toast.saved"), { closeButton: true });
       queryClient.invalidateQueries({ queryKey: ["proxyConfig"] });
       queryClient.invalidateQueries({ queryKey: ["proxyStatus"] });
     },
     onError: (error: Error) => {
-      toast.error(`保存失败: ${error.message}`);
+      toast.error(
+        t("proxy.settings.toast.saveFailed", {
+          error: error.message,
+        }),
+      );
     },
   });
 

src/hooks/useProxyStatus.ts

@@ -50,7 +50,8 @@ export function useProxyStatus() {
       queryClient.invalidateQueries({ queryKey: ["proxyStatus"] });
     },
     onError: (error: Error) => {
-      const detail = extractErrorMessage(error) || "未知错误";
+      const detail =
+        extractErrorMessage(error) || t("common.unknown", { defaultValue: "未知错误" });
       toast.error(
         t("proxy.server.startFailed", {
           defaultValue: `启动代理服务失败: ${detail}`,
@@ -75,7 +76,8 @@ export function useProxyStatus() {
       queryClient.invalidateQueries({ queryKey: ["providerHealth"] });
     },
     onError: (error: Error) => {
-      const detail = extractErrorMessage(error) || "未知错误";
+      const detail =
+        extractErrorMessage(error) || t("common.unknown", { defaultValue: "未知错误" });
       toast.error(
         t("proxy.stopWithRestoreFailed", {
           defaultValue: `停止失败: ${detail}`,
@@ -111,7 +113,8 @@ export function useProxyStatus() {
       queryClient.invalidateQueries({ queryKey: ["proxyTakeoverStatus"] });
     },
     onError: (error: Error) => {
-      const detail = extractErrorMessage(error) || "未知错误";
+      const detail =
+        extractErrorMessage(error) || t("common.unknown", { defaultValue: "未知错误" });
       toast.error(
         t("proxy.takeover.failed", {
           defaultValue: `操作失败: ${detail}`,
@@ -133,8 +136,14 @@ export function useProxyStatus() {
       queryClient.invalidateQueries({ queryKey: ["proxyStatus"] });
     },
     onError: (error: Error) => {
-      const detail = extractErrorMessage(error) || "未知错误";
-      toast.error(`切换失败: ${detail}`);
+      const detail =
+        extractErrorMessage(error) || t("common.unknown", { defaultValue: "未知错误" });
+      toast.error(
+        t("proxy.switchFailed", {
+          error: detail,
+          defaultValue: `切换失败: ${detail}`,
+        }),
+      );
     },
   });