feat(search): add Xquik as an X search provider

Xquik needs a GET request with x-api-key auth and a tweets envelope
normalizer, neither of which the generic search fallback provides. Adds a
dedicated request builder and normalizer, cursor pagination passthrough,
result-based credit usage reporting, and a validateUrl probe so key
validation hits the no-charge credits endpoint.

tests/unit/xquik-search-provider.test.js

@@ -0,0 +1,154 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+import REGISTRY from "../../open-sse/providers/registry/index.js";
+import { buildSearchRequest } from "../../open-sse/handlers/search/callers.js";
+import { handleSearchCore } from "../../open-sse/handlers/search/index.js";
+import { normalizeSearchResponse } from "../../open-sse/handlers/search/normalizers.js";
+import { AI_PROVIDERS, getProvidersByKind } from "@/shared/constants/providers.js";
+
+const CONFIG = {
+  id: "xquik",
+  baseUrl: "https://xquik.com/api/v1/x/tweets/search",
+  method: "GET",
+  authType: "apikey",
+  searchTypes: ["x"],
+  defaultMaxResults: 5,
+  maxMaxResults: 100,
+  creditsPerResult: 1,
+};
+
+const PARAMS = {
+  query: "from:github release notes",
+  searchType: "x",
+  maxResults: 10,
+  token: "xq_test_key",
+  language: "en",
+  providerOptions: { queryType: "Latest", cursor: "next page" },
+};
+
+const RESPONSE = {
+  tweets: [
+    {
+      id: "1234567890",
+      text: "Release notes are live.",
+      createdAt: "2026-08-25T12:00:00Z",
+      author: { username: "github", name: "GitHub" },
+      media: [{ mediaUrl: "https://pbs.twimg.com/media/example.jpg", type: "photo" }],
+    },
+  ],
+  has_next_page: true,
+  next_cursor: "cursor-2",
+};
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+});
+
+describe("Xquik search provider", () => {
+  it("registers a dedicated X search provider with no-charge key validation", () => {
+    const entry = REGISTRY.find((candidate) => candidate.id === "xquik");
+
+    expect(entry).toMatchObject({
+      category: "apikey",
+      serviceKinds: ["webSearch"],
+      searchConfig: {
+        authHeader: "x-api-key",
+        validateUrl: "https://xquik.com/api/v1/credits",
+        searchTypes: ["x"],
+        creditsPerResult: 1,
+      },
+    });
+    expect(AI_PROVIDERS.xquik?.searchConfig).toEqual(entry.searchConfig);
+    expect(getProvidersByKind("webSearch").map((provider) => provider.id)).toContain("xquik");
+  });
+
+  it("builds the documented GET request without putting the key in the URL", () => {
+    const request = buildSearchRequest(CONFIG, PARAMS);
+    const url = new URL(request.url);
+
+    expect(url.origin + url.pathname).toBe("https://xquik.com/api/v1/x/tweets/search");
+    expect(Object.fromEntries(url.searchParams)).toEqual({
+      q: "from:github release notes",
+      limit: "10",
+      cursor: "next page",
+      queryType: "Latest",
+      language: "en",
+    });
+    expect(url.search).not.toContain("xq_test_key");
+    expect(request.init).toEqual({
+      method: "GET",
+      headers: { Accept: "application/json", "x-api-key": "xq_test_key" },
+    });
+  });
+
+  it("rejects unsupported query types before contacting Xquik", () => {
+    expect(() => buildSearchRequest(CONFIG, {
+      ...PARAMS,
+      providerOptions: { queryType: "Popular" },
+    })).toThrow("Xquik queryType must be Latest or Top");
+  });
+
+  it("normalizes posts and preserves cursor pagination", () => {
+    const normalized = normalizeSearchResponse("xquik", RESPONSE, PARAMS.query, "x");
+
+    expect(normalized.totalResults).toBeNull();
+    expect(normalized.pagination).toEqual({ has_more: true, next_cursor: "cursor-2" });
+    expect(normalized.results).toHaveLength(1);
+    expect(normalized.results[0]).toMatchObject({
+      title: "@github on X",
+      url: "https://x.com/github/status/1234567890",
+      display_url: "x.com/github/status/1234567890",
+      snippet: "Release notes are live.",
+      published_at: "2026-08-25T12:00:00Z",
+      metadata: {
+        author: "@github",
+        source_type: "x_post",
+        image_url: "https://pbs.twimg.com/media/example.jpg",
+      },
+      citation: { provider: "xquik", rank: 1 },
+    });
+    expect(normalized.results[0].content).toEqual({
+      format: "text",
+      text: "Release notes are live.",
+      length: 23,
+    });
+  });
+
+  it("uses the stable status URL when author data is unavailable", () => {
+    const normalized = normalizeSearchResponse("xquik", {
+      tweets: [{ id: "9876543210", text: "Author data is unavailable." }],
+      has_next_page: false,
+      next_cursor: "",
+    }, PARAMS.query, "x");
+
+    expect(normalized.results[0]).toMatchObject({
+      title: "X post",
+      url: "https://x.com/i/web/status/9876543210",
+      metadata: { author: null, source_type: "x_post" },
+    });
+    expect(normalized.pagination).toEqual({ has_more: false, next_cursor: null });
+  });
+
+  it("reports Xquik credits without claiming an unknown USD cost", async () => {
+    vi.stubGlobal("fetch", vi.fn(async () => new Response(JSON.stringify(RESPONSE), {
+      status: 200,
+      headers: { "Content-Type": "application/json" },
+    })));
+
+    const result = await handleSearchCore({
+      body: { query: PARAMS.query, max_results: 10, provider_options: PARAMS.providerOptions },
+      provider: { id: "xquik" },
+      providerConfig: CONFIG,
+      credentials: { apiKey: "xq_test_key" },
+    });
+    const payload = await result.response.json();
+
+    expect(result.success).toBe(true);
+    expect(payload.usage).toEqual({
+      queries_used: 1,
+      search_cost_usd: null,
+      provider_credits_used: 1,
+    });
+    expect(payload.pagination).toEqual({ has_more: true, next_cursor: "cursor-2" });
+  });
+});