feat(memory): native Voyage AI support (#7078)

* feat(memory): add native Voyage AI embedding support with batching

Cherry-picked from PR #2519, resolved conflict in memory-search.ts
(hasRemote -> hasRemoteConfig rename + added voyage provider)

* fix(memory): optimize voyage batch memory usage with streaming and deduplicate code

Cherry-picked from PR #2519. Fixed lint error: changed this.runWithConcurrency
to use imported runWithConcurrency function after extraction to internal.ts

src/memory/embeddings-voyage.test.ts

@@ -0,0 +1,100 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("../agents/model-auth.js", () => ({
+  resolveApiKeyForProvider: vi.fn(),
+  requireApiKey: (auth: { apiKey?: string; mode?: string }, provider: string) => {
+    if (auth?.apiKey) return auth.apiKey;
+    throw new Error(`No API key resolved for provider "${provider}" (auth mode: ${auth?.mode}).`);
+  },
+}));
+
+const createFetchMock = () =>
+  vi.fn(async () => ({
+    ok: true,
+    status: 200,
+    json: async () => ({ data: [{ embedding: [0.1, 0.2, 0.3] }] }),
+  })) as unknown as typeof fetch;
+
+describe("voyage embedding provider", () => {
+  afterEach(() => {
+    vi.resetAllMocks();
+    vi.resetModules();
+    vi.unstubAllGlobals();
+  });
+
+  it("configures client with correct defaults and headers", async () => {
+    const fetchMock = createFetchMock();
+    vi.stubGlobal("fetch", fetchMock);
+
+    const { createVoyageEmbeddingProvider } = await import("./embeddings-voyage.js");
+    const authModule = await import("../agents/model-auth.js");
+
+    vi.mocked(authModule.resolveApiKeyForProvider).mockResolvedValue({
+      apiKey: "voyage-key-123",
+      mode: "api-key",
+      source: "test",
+    });
+
+    const result = await createVoyageEmbeddingProvider({
+      config: {} as never,
+      provider: "voyage",
+      model: "voyage-4-large",
+      fallback: "none",
+    });
+
+    await result.provider.embedQuery("test query");
+
+    expect(authModule.resolveApiKeyForProvider).toHaveBeenCalledWith(
+      expect.objectContaining({ provider: "voyage" }),
+    );
+
+    const [url, init] = fetchMock.mock.calls[0] ?? [];
+    expect(url).toBe("https://api.voyageai.com/v1/embeddings");
+
+    const headers = (init?.headers ?? {}) as Record<string, string>;
+    expect(headers.Authorization).toBe("Bearer voyage-key-123");
+    expect(headers["Content-Type"]).toBe("application/json");
+
+    const body = JSON.parse(init?.body as string);
+    expect(body).toEqual({
+      model: "voyage-4-large",
+      input: ["test query"],
+    });
+  });
+
+  it("respects remote overrides for baseUrl and apiKey", async () => {
+    const fetchMock = createFetchMock();
+    vi.stubGlobal("fetch", fetchMock);
+
+    const { createVoyageEmbeddingProvider } = await import("./embeddings-voyage.js");
+
+    const result = await createVoyageEmbeddingProvider({
+      config: {} as never,
+      provider: "voyage",
+      model: "voyage-4-lite",
+      fallback: "none",
+      remote: {
+        baseUrl: "https://proxy.example.com",
+        apiKey: "remote-override-key",
+        headers: { "X-Custom": "123" },
+      },
+    });
+
+    await result.provider.embedQuery("test");
+
+    const [url, init] = fetchMock.mock.calls[0] ?? [];
+    expect(url).toBe("https://proxy.example.com/embeddings");
+
+    const headers = (init?.headers ?? {}) as Record<string, string>;
+    expect(headers.Authorization).toBe("Bearer remote-override-key");
+    expect(headers["X-Custom"]).toBe("123");
+  });
+
+  it("normalizes model names", async () => {
+    const { normalizeVoyageModel } = await import("./embeddings-voyage.js");
+    expect(normalizeVoyageModel("voyage/voyage-large-2")).toBe("voyage-large-2");
+    expect(normalizeVoyageModel("voyage-4-large")).toBe("voyage-4-large");
+    expect(normalizeVoyageModel("  voyage-lite  ")).toBe("voyage-lite");
+    expect(normalizeVoyageModel("")).toBe("voyage-4-large"); // Default
+  });
+});