refactor(plugins): register provider model id hooks

src/agents/model-selection.plugin-runtime.test.ts

@@ -0,0 +1,41 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const normalizeProviderModelIdWithPluginMock = vi.fn();
+
+vi.mock("../plugins/provider-runtime.js", () => ({
+  normalizeProviderModelIdWithPlugin: (params: unknown) =>
+    normalizeProviderModelIdWithPluginMock(params),
+}));
+
+describe("model-selection plugin runtime normalization", () => {
+  beforeEach(() => {
+    vi.resetModules();
+    normalizeProviderModelIdWithPluginMock.mockReset();
+  });
+
+  it("delegates provider-owned model id normalization to plugin runtime hooks", async () => {
+    normalizeProviderModelIdWithPluginMock.mockImplementation(({ provider, context }) => {
+      if (
+        provider === "xai" &&
+        (context as { modelId?: string }).modelId === "grok-4.20-experimental-beta-0304-reasoning"
+      ) {
+        return "grok-4.20-beta-latest-reasoning";
+      }
+      return undefined;
+    });
+
+    const { parseModelRef } = await import("./model-selection.js");
+
+    expect(parseModelRef("grok-4.20-experimental-beta-0304-reasoning", "xai")).toEqual({
+      provider: "xai",
+      model: "grok-4.20-beta-latest-reasoning",
+    });
+    expect(normalizeProviderModelIdWithPluginMock).toHaveBeenCalledWith({
+      provider: "xai",
+      context: {
+        provider: "xai",
+        modelId: "grok-4.20-experimental-beta-0304-reasoning",
+      },
+    });
+  });
+});