Fix Kimi and Xiaomi model metadata

Closes #5075, closes #5078. Refs #5087.

packages/ai/test/xiaomi-models.test.ts

@@ -0,0 +1,15 @@
+import { describe, expect, it } from "vitest";
+import { getModel, getModels } from "../src/models.ts";
+
+describe("Xiaomi MiMo models", () => {
+	it("keeps mimo-v2-flash on the API billing provider", () => {
+		expect(getModel("xiaomi", "mimo-v2-flash")).toBeDefined();
+	});
+
+	it.each(["xiaomi-token-plan-cn", "xiaomi-token-plan-ams", "xiaomi-token-plan-sgp"] as const)(
+		"omits mimo-v2-flash from %s",
+		(provider) => {
+			expect(getModels(provider).some((model) => model.id === "mimo-v2-flash")).toBe(false);
+		},
+	);
+});