Add docs i18n support

.changeset/i18n-docs-support.md

@@ -0,0 +1,5 @@
+---
+"leadtype": patch
+---
+
+Add first-class docs i18n support with locale-aware generation, localized source loading, per-locale search/LLM/readability artifacts, and a new `leadtype/i18n` helper surface. Locale-scoped search generation now uses URL-path document ids to align generated indexes with the source API.

package.json

@@ -3,10 +3,11 @@
     "@biomejs/biome": "2.4.14",
     "@changesets/changelog-github": "0.7.0",
     "@changesets/cli": "2.31.0",
-    "leadtype": "workspace:*",
     "@mdx-js/react": "^3.1.1",
     "@typescript/native-preview": "7.0.0-dev.20260509.2",
+    "@vitest/coverage-v8": "4.1.5",
     "husky": "^9.1.7",
+    "leadtype": "workspace:*",
     "turbo": "^2.9.12",
     "typescript": "6.0.3",
     "ultracite": "7.6.5"

packages/leadtype/package.json

@@ -33,6 +33,10 @@
       "types": "./dist/fumadocs/index.d.ts",
       "import": "./dist/fumadocs/index.js"
     },
+    "./i18n": {
+      "types": "./dist/i18n/index.d.ts",
+      "import": "./dist/i18n/index.js"
+    },
     "./remark": {
       "types": "./dist/remark/index.d.ts",
       "import": "./dist/remark/index.js"

packages/leadtype/rollup.config.ts

@@ -7,6 +7,7 @@ const entries = {
   index: "src/index.ts",
   "mdx/index": "src/mdx/index.ts",
   "fumadocs/index": "src/fumadocs/index.ts",
+  "i18n/index": "src/i18n/index.ts",
   "remark/index": "src/remark/index.ts",
   "convert/index": "src/convert/index.ts",
   "llm/index": "src/llm/index.ts",

packages/leadtype/src/cli.test.ts

@@ -327,6 +327,97 @@ describe("leadtype CLI", () => {
     );
   });
 
+  it("generates locale-scoped i18n artifacts while keeping default URLs stable", async () => {
+    const srcDir = await createTempDir();
+    const outDir = await createTempDir();
+    const capture = createCapture();
+
+    await mkdir(path.join(srcDir, "docs"), { recursive: true });
+    await writeFile(
+      path.join(srcDir, "docs", "docs.config.ts"),
+      `export default {
+  product: {
+    name: "Localized Product",
+    summary: "Localized product summary.",
+  },
+  groups: [{ slug: "get-started", title: "Get Started" }],
+  i18n: {
+    defaultLocale: "en",
+    locales: ["en", "zh"],
+  },
+};`
+    );
+    await writeMdxPage(
+      srcDir,
+      "quickstart.mdx",
+      'title: "Quickstart"\ndescription: "English quickstart."\ngroup: get-started',
+      "English body."
+    );
+    await writeMdxPage(
+      srcDir,
+      "setup.mdx",
+      'title: "Setup"\ndescription: "English setup."\ngroup: get-started',
+      "English setup."
+    );
+    await writeMdxPage(
+      srcDir,
+      "zh/quickstart.mdx",
+      'title: "快速开始"\ndescription: "中文快速开始。"\ngroup: get-started',
+      "中文正文。"
+    );
+
+    const code = await runCli(
+      ["generate", "--src", srcDir, "--out", outDir, "--format", "json"],
+      capture.io
+    );
+
+    expect(code).toBe(0);
+    const result = JSON.parse(capture.stdout) as {
+      files: { i18nManifest?: string };
+    };
+    expect(result.files.i18nManifest).toBe(
+      path.join(outDir, "docs", "i18n-manifest.json")
+    );
+
+    const manifest = JSON.parse(
+      await readFile(path.join(outDir, "docs", "i18n-manifest.json"), "utf8")
+    ) as {
+      defaultLocale: string;
+      artifacts: Array<{ locale: string; searchIndex: string }>;
+    };
+    expect(manifest.defaultLocale).toBe("en");
+    expect(manifest.artifacts).toContainEqual(
+      expect.objectContaining({
+        locale: "zh",
+        searchIndex: "/docs/zh/search-index.json",
+      })
+    );
+
+    const defaultSummary = await readFile(
+      path.join(outDir, "docs", "llms.txt"),
+      "utf8"
+    );
+    expect(defaultSummary).toContain("](/docs/quickstart.md)");
+
+    const zhSummary = await readFile(
+      path.join(outDir, "docs", "zh", "llms.txt"),
+      "utf8"
+    );
+    expect(zhSummary).toContain("快速开始");
+    expect(zhSummary).toContain("](/docs/zh/quickstart.md)");
+    expect(zhSummary).not.toContain("Setup");
+
+    const zhSearch = JSON.parse(
+      await readFile(
+        path.join(outDir, "docs", "zh", "search-index.json"),
+        "utf8"
+      )
+    ) as { documents: [string, string, string, string][] };
+    expect(zhSearch.documents.map((entry) => entry[3])).toEqual([
+      "/docs/zh/quickstart",
+    ]);
+  });
+
   it("lets --name and --summary override docs config product fields", async () => {
     const srcDir = await createTempDir();
     const outDir = await createTempDir();