feat(xiaomi-tokenplan): add Claude-native MiMo V2.5 Pro alias via dedicated executor

Add mimo-v2.5-pro-claude alias routing to the Xiaomi TokenPlan Anthropic-compatible
/anthropic/v1/messages endpoint. Logic lives in a dedicated XiaomiTokenplanExecutor
(config-driven via targetFormat) instead of the shared DefaultExecutor.

Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/executors/default.js

@@ -1,5 +1,5 @@
 import { BaseExecutor } from "./base.js";
-import { PROVIDERS, resolveXiaomiTokenplanBaseUrl } from "../config/providers.js";
+import { PROVIDERS } from "../config/providers.js";
 import { OAUTH_ENDPOINTS, buildKimiHeaders } from "../config/appConstants.js";
 import { buildClineHeaders } from "../../src/shared/utils/clineAuth.js";
 import { getCachedClaudeHeaders } from "../utils/claudeHeaderCache.js";
@@ -60,9 +60,6 @@ export class DefaultExecutor extends BaseExecutor {
       case "gemini":
         return `${this.config.baseUrl}/${model}:${stream ? "streamGenerateContent?alt=sse" : "generateContent"}`;
       default: {
-        if (this.provider === "xiaomi-tokenplan") {
-          return `${resolveXiaomiTokenplanBaseUrl(credentials)}/chat/completions`;
-        }
         const url = this.config.baseUrl;
         if (url?.includes("{accountId}")) {
           const accountId = credentials?.providerSpecificData?.accountId;