refactor: move memory engine behind plugin adapters

src/plugins/memory-embedding-providers.test.ts

@@ -0,0 +1,49 @@
+import { afterEach, describe, expect, it } from "vitest";
+import {
+  clearMemoryEmbeddingProviders,
+  getMemoryEmbeddingProvider,
+  listMemoryEmbeddingProviders,
+  registerMemoryEmbeddingProvider,
+  restoreMemoryEmbeddingProviders,
+  type MemoryEmbeddingProviderAdapter,
+} from "./memory-embedding-providers.js";
+
+function createAdapter(id: string): MemoryEmbeddingProviderAdapter {
+  return {
+    id,
+    create: async () => ({ provider: null }),
+  };
+}
+
+afterEach(() => {
+  clearMemoryEmbeddingProviders();
+});
+
+describe("memory embedding provider registry", () => {
+  it("registers and lists adapters in insertion order", () => {
+    registerMemoryEmbeddingProvider(createAdapter("alpha"));
+    registerMemoryEmbeddingProvider(createAdapter("beta"));
+
+    expect(getMemoryEmbeddingProvider("alpha")?.id).toBe("alpha");
+    expect(listMemoryEmbeddingProviders().map((adapter) => adapter.id)).toEqual(["alpha", "beta"]);
+  });
+
+  it("restores a previous snapshot", () => {
+    const alpha = createAdapter("alpha");
+    const beta = createAdapter("beta");
+    registerMemoryEmbeddingProvider(alpha);
+
+    restoreMemoryEmbeddingProviders([beta]);
+
+    expect(getMemoryEmbeddingProvider("alpha")).toBeUndefined();
+    expect(getMemoryEmbeddingProvider("beta")).toBe(beta);
+  });
+
+  it("clears the registry", () => {
+    registerMemoryEmbeddingProvider(createAdapter("alpha"));
+
+    clearMemoryEmbeddingProviders();
+
+    expect(listMemoryEmbeddingProviders()).toEqual([]);
+  });
+});