feat: add Xiaomi MiMo provider onboarding (#3454)

Thanks @WqyJh.

Co-authored-by: Qiying Wang <15232241+WqyJh@users.noreply.github.com>

src/commands/onboard-auth.test.ts

@@ -15,6 +15,8 @@ import {
   applyOpenrouterProviderConfig,
   applySyntheticConfig,
   applySyntheticProviderConfig,
+  applyXiaomiConfig,
+  applyXiaomiProviderConfig,
   OPENROUTER_DEFAULT_MODEL_REF,
   SYNTHETIC_DEFAULT_MODEL_ID,
   SYNTHETIC_DEFAULT_MODEL_REF,
@@ -343,6 +345,50 @@ describe("applySyntheticConfig", () => {
   });
 });
 
+describe("applyXiaomiConfig", () => {
+  it("adds Xiaomi provider with correct settings", () => {
+    const cfg = applyXiaomiConfig({});
+    expect(cfg.models?.providers?.xiaomi).toMatchObject({
+      baseUrl: "https://api.xiaomimimo.com/anthropic",
+      api: "anthropic-messages",
+    });
+    expect(cfg.agents?.defaults?.model?.primary).toBe("xiaomi/mimo-v2-flash");
+  });
+
+  it("merges Xiaomi models and keeps existing provider overrides", () => {
+    const cfg = applyXiaomiProviderConfig({
+      models: {
+        providers: {
+          xiaomi: {
+            baseUrl: "https://old.example.com",
+            apiKey: "old-key",
+            api: "openai-completions",
+            models: [
+              {
+                id: "custom-model",
+                name: "Custom",
+                reasoning: false,
+                input: ["text"],
+                cost: { input: 1, output: 2, cacheRead: 0, cacheWrite: 0 },
+                contextWindow: 1000,
+                maxTokens: 100,
+              },
+            ],
+          },
+        },
+      },
+    });
+
+    expect(cfg.models?.providers?.xiaomi?.baseUrl).toBe("https://api.xiaomimimo.com/anthropic");
+    expect(cfg.models?.providers?.xiaomi?.api).toBe("anthropic-messages");
+    expect(cfg.models?.providers?.xiaomi?.apiKey).toBe("old-key");
+    expect(cfg.models?.providers?.xiaomi?.models.map((m) => m.id)).toEqual([
+      "custom-model",
+      "mimo-v2-flash",
+    ]);
+  });
+});
+
 describe("applyOpencodeZenProviderConfig", () => {
   it("adds allowlist entry for the default model", () => {
     const cfg = applyOpencodeZenProviderConfig({});