feat(claude): add API format selector for third-party providers

Replace the OpenRouter-specific compatibility toggle with a generic
API format selector that allows all Claude providers to choose between:

- Anthropic Messages (native): Direct passthrough, no conversion
- OpenAI Chat Completions: Enables Anthropic ↔ OpenAI format conversion

Changes:
- Add ClaudeApiFormat type ("anthropic" | "openai_chat") to types.ts
- Replace openRouterCompatToggle with apiFormat dropdown in ClaudeFormFields
- Update ProviderForm to manage apiFormat state via settingsConfig.api_format
- Refactor claude.rs: add get_api_format() method, update needs_transform()
- Maintain backward compatibility with legacy openrouter_compat_mode field
- Update i18n translations (zh, en, ja)

src/components/providers/forms/ClaudeFormFields.tsx

@@ -1,10 +1,16 @@
 import { useTranslation } from "react-i18next";
 import { FormLabel } from "@/components/ui/form";
-import { Switch } from "@/components/ui/switch";
 import { Input } from "@/components/ui/input";
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/components/ui/select";
 import EndpointSpeedTest from "./EndpointSpeedTest";
 import { ApiKeySection, EndpointField } from "./shared";
-import type { ProviderCategory } from "@/types";
+import type { ProviderCategory, ClaudeApiFormat } from "@/types";
 import type { TemplateValueConfig } from "@/config/claudeProviderPresets";
 
 interface EndpointCandidate {
@@ -59,10 +65,9 @@ interface ClaudeFormFieldsProps {
   // Speed Test Endpoints
   speedTestEndpoints: EndpointCandidate[];
 
-  // OpenRouter Compat
-  showOpenRouterCompatToggle: boolean;
-  openRouterCompatEnabled: boolean;
-  onOpenRouterCompatChange: (enabled: boolean) => void;
+  // API Format (for third-party providers that use OpenAI Chat Completions format)
+  apiFormat: ClaudeApiFormat;
+  onApiFormatChange: (format: ClaudeApiFormat) => void;
 }
 
 export function ClaudeFormFields({
@@ -95,9 +100,8 @@ export function ClaudeFormFields({
   defaultOpusModel,
   onModelChange,
   speedTestEndpoints,
-  showOpenRouterCompatToggle,
-  openRouterCompatEnabled,
-  onOpenRouterCompatChange,
+  apiFormat,
+  onApiFormatChange,
 }: ClaudeFormFieldsProps) {
   const { t } = useTranslation();
 
@@ -180,25 +184,34 @@ export function ClaudeFormFields({
         />
       )}
 
-      {showOpenRouterCompatToggle && (
-        <div className="flex items-center justify-between rounded-lg border border-white/10 bg-background/60 p-4">
-          <div className="space-y-1">
-            <FormLabel>
-              {t("providerForm.openrouterCompatMode", {
-                defaultValue: "OpenRouter 兼容模式",
-              })}
-            </FormLabel>
-            <p className="text-xs text-muted-foreground">
-              {t("providerForm.openrouterCompatModeHint", {
-                defaultValue:
-                  "使用 OpenAI Chat Completions 接口并转换为 Anthropic SSE。",
-              })}
-            </p>
-          </div>
-          <Switch
-            checked={openRouterCompatEnabled}
-            onCheckedChange={onOpenRouterCompatChange}
-          />
+      {/* API 格式选择（仅非官方供应商显示） */}
+      {shouldShowModelSelector && (
+        <div className="space-y-2">
+          <FormLabel htmlFor="apiFormat">
+            {t("providerForm.apiFormat", { defaultValue: "API 格式" })}
+          </FormLabel>
+          <Select value={apiFormat} onValueChange={onApiFormatChange}>
+            <SelectTrigger id="apiFormat" className="w-full">
+              <SelectValue />
+            </SelectTrigger>
+            <SelectContent>
+              <SelectItem value="anthropic">
+                {t("providerForm.apiFormatAnthropic", {
+                  defaultValue: "Anthropic Messages (原生)",
+                })}
+              </SelectItem>
+              <SelectItem value="openai_chat">
+                {t("providerForm.apiFormatOpenAIChat", {
+                  defaultValue: "OpenAI Chat Completions (需转换)",
+                })}
+              </SelectItem>
+            </SelectContent>
+          </Select>
+          <p className="text-xs text-muted-foreground">
+            {t("providerForm.apiFormatHint", {
+              defaultValue: "选择供应商 API 的输入格式",
+            })}
+          </p>
         </div>
       )}
 

src/components/providers/forms/ProviderForm.tsx

@@ -13,6 +13,7 @@ import type {
   ProviderMeta,
   ProviderTestConfig,
   ProviderProxyConfig,
+  ClaudeApiFormat,
 } from "@/types";
 import {
   providerPresets,
@@ -284,45 +285,31 @@ export function ProviderForm({
     onConfigChange: (config) => form.setValue("settingsConfig", config),
   });
 
-  const isOpenRouterProvider = useMemo(() => {
-    if (appId !== "claude") return false;
-    const normalized = baseUrl.trim().toLowerCase();
-    if (normalized.includes("openrouter.ai")) {
-      return true;
-    }
+  // Claude API Format state
+  // Read initial value from settingsConfig.api_format, default to "anthropic"
+  const apiFormat = useMemo<ClaudeApiFormat>(() => {
+    if (appId !== "claude") return "anthropic";
     try {
       const config = JSON.parse(settingsConfigValue || "{}");
-      const envUrl = config?.env?.ANTHROPIC_BASE_URL;
-      return typeof envUrl === "string" && envUrl.includes("openrouter.ai");
-    } catch {
-      return false;
-    }
-  }, [appId, baseUrl, settingsConfigValue]);
-
-  const openRouterCompatEnabled = useMemo(() => {
-    if (!isOpenRouterProvider) return false;
-    try {
-      const config = JSON.parse(settingsConfigValue || "{}");
-      const raw = config?.openrouter_compat_mode;
-      if (typeof raw === "boolean") return raw;
-      if (typeof raw === "number") return raw !== 0;
-      if (typeof raw === "string") {
-        const normalized = raw.trim().toLowerCase();
-        return normalized === "true" || normalized === "1";
-      }
+      const format = config?.api_format;
+      if (format === "openai_chat") return "openai_chat";
+      // Backward compatibility: if old openrouter_compat_mode is true, treat as openai_chat
+      if (config?.openrouter_compat_mode === true) return "openai_chat";
     } catch {
       // ignore
     }
-    return false; // OpenRouter now supports Claude Code compatible API, no need for transform
-  }, [isOpenRouterProvider, settingsConfigValue]);
+    return "anthropic";
+  }, [appId, settingsConfigValue]);
 
-  const handleOpenRouterCompatChange = useCallback(
-    (enabled: boolean) => {
+  const handleApiFormatChange = useCallback(
+    (format: ClaudeApiFormat) => {
       try {
         const currentConfig = JSON.parse(
           form.getValues("settingsConfig") || "{}",
         );
-        currentConfig.openrouter_compat_mode = enabled;
+        currentConfig.api_format = format;
+        // Clean up legacy field
+        delete currentConfig.openrouter_compat_mode;
         form.setValue("settingsConfig", JSON.stringify(currentConfig, null, 2));
       } catch {
         // ignore
@@ -1294,9 +1281,8 @@ export function ProviderForm({
             defaultOpusModel={defaultOpusModel}
             onModelChange={handleModelChange}
             speedTestEndpoints={speedTestEndpoints}
-            showOpenRouterCompatToggle={false}
-            openRouterCompatEnabled={openRouterCompatEnabled}
-            onOpenRouterCompatChange={handleOpenRouterCompatChange}
+            apiFormat={apiFormat}
+            onApiFormatChange={handleApiFormatChange}
           />
         )}
 

src/i18n/locales/en.json

@@ -472,8 +472,10 @@
     "anthropicModel": "Main Model",
     "anthropicSmallFastModel": "Fast Model",
     "anthropicReasoningModel": "Reasoning Model (Thinking)",
-    "openrouterCompatMode": "OpenRouter Compatibility Mode",
-    "openrouterCompatModeHint": "Use OpenAI Chat Completions interface and convert to Anthropic SSE.",
+    "apiFormat": "API Format",
+    "apiFormatHint": "Select the input format for the provider's API",
+    "apiFormatAnthropic": "Anthropic Messages (Native)",
+    "apiFormatOpenAIChat": "OpenAI Chat Completions (Requires conversion)",
     "anthropicDefaultHaikuModel": "Default Haiku Model",
     "anthropicDefaultSonnetModel": "Default Sonnet Model",
     "anthropicDefaultOpusModel": "Default Opus Model",

src/i18n/locales/ja.json

@@ -472,8 +472,10 @@
     "anthropicModel": "メインモデル",
     "anthropicSmallFastModel": "高速モデル",
     "anthropicReasoningModel": "推論モデル（Thinking）",
-    "openrouterCompatMode": "OpenRouter 互換モード",
-    "openrouterCompatModeHint": "OpenAI Chat Completions インターフェースを使用し、Anthropic SSE に変換します。",
+    "apiFormat": "API フォーマット",
+    "apiFormatHint": "プロバイダー API の入力フォーマットを選択",
+    "apiFormatAnthropic": "Anthropic Messages（ネイティブ）",
+    "apiFormatOpenAIChat": "OpenAI Chat Completions（変換が必要）",
     "anthropicDefaultHaikuModel": "既定 Haiku モデル",
     "anthropicDefaultSonnetModel": "既定 Sonnet モデル",
     "anthropicDefaultOpusModel": "既定 Opus モデル",

src/i18n/locales/zh.json

@@ -472,8 +472,10 @@
     "anthropicModel": "主模型",
     "anthropicSmallFastModel": "快速模型",
     "anthropicReasoningModel": "推理模型 (Thinking)",
-    "openrouterCompatMode": "OpenRouter 兼容模式",
-    "openrouterCompatModeHint": "使用 OpenAI Chat Completions 接口并转换为 Anthropic SSE。",
+    "apiFormat": "API 格式",
+    "apiFormatHint": "选择供应商 API 的输入格式",
+    "apiFormatAnthropic": "Anthropic Messages (原生)",
+    "apiFormatOpenAIChat": "OpenAI Chat Completions (需转换)",
     "anthropicDefaultHaikuModel": "Haiku 默认模型",
     "anthropicDefaultSonnetModel": "Sonnet 默认模型",
     "anthropicDefaultOpusModel": "Opus 默认模型",

src/types.ts

@@ -144,6 +144,11 @@ export interface ProviderMeta {
 // Skill 同步方式
 export type SkillSyncMethod = "auto" | "symlink" | "copy";
 
+// Claude API 格式类型
+// - "anthropic": 原生 Anthropic Messages API 格式，直接透传
+// - "openai_chat": OpenAI Chat Completions 格式，需要格式转换
+export type ClaudeApiFormat = "anthropic" | "openai_chat";
+
 // 主页面显示的应用配置
 export interface VisibleApps {
   claude: boolean;