Initialize repository with harness code and assets

Initial import of all source code, config, and README assets: the
packages workspace (cli, core, server, web, docs, landing, skills),
build scripts, tooling config, and CI workflows.

Includes the data-layout revision made on this branch: the local data
root defaults to ~/.penguin/data (PENGUIN_HOME still overrides; the
installer keeps its binaries in ~/.penguin), and every Agent lives
under <project>/agents/<agent>/ — path helpers, the three
agent-enumeration scans, the system prompt, built-in Skills, tests
and docs all follow the new layout.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018ihk8iQuo3kv2aPjAYEPuR

packages/docs/test/content.test.ts

@@ -0,0 +1,41 @@
+/**
+ * Content integrity: the sidebar (DOCS_NAV) and the content/ directory must agree —
+ * every navigated slug has both zh and en files with a frontmatter title, and every
+ * content file belongs to the navigation (an orphan file would be unreachable).
+ * Reads the files via fs so the check runs under plain node (no Vite glob).
+ */
+import { readdirSync, readFileSync } from "node:fs";
+import { join } from "node:path";
+import { describe, expect, it } from "vitest";
+import { DOCS_NAV, DOC_SLUGS } from "../src/lib/nav";
+import { parseFrontmatter } from "../src/lib/frontmatter";
+
+const contentDir = join(__dirname, "..", "content");
+const files = readdirSync(contentDir).filter((f) => f.endsWith(".md"));
+
+describe("docs navigation / content integrity", () => {
+  it("has unique slugs in DOCS_NAV", () => {
+    expect(new Set(DOC_SLUGS).size).toBe(DOC_SLUGS.length);
+    expect(DOCS_NAV.length).toBeGreaterThan(0);
+  });
+
+  it("provides zh and en files with a title for every navigated slug", () => {
+    for (const slug of DOC_SLUGS) {
+      for (const lang of ["zh", "en"] as const) {
+        const name = `${slug}.${lang}.md`;
+        expect(files, `missing content file ${name}`).toContain(name);
+        const { meta, body } = parseFrontmatter(readFileSync(join(contentDir, name), "utf8"));
+        expect(meta.title, `missing title in ${name}`).toBeTruthy();
+        expect(body.length, `empty body in ${name}`).toBeGreaterThan(0);
+      }
+    }
+  });
+
+  it("has no content file outside the navigation", () => {
+    for (const file of files) {
+      const slug = /^(.+)\.(zh|en)\.md$/.exec(file)?.[1];
+      expect(slug, `unparsable content file name ${file}`).toBeTruthy();
+      expect(DOC_SLUGS, `orphan content file ${file}`).toContain(slug!);
+    }
+  });
+});