Add /help routes to display README documentation

Provides /help index and /help/{doc_name} routes to view
L1 server and Common library READMEs in the web UI.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

server.py

@@ -3682,6 +3682,84 @@ async def download_client():
     )
 
 
+# ============================================================================
+# Help / Documentation Routes
+# ============================================================================
+
+L2_DOCS_DIR = Path(__file__).parent
+COMMON_DOCS_DIR = Path(__file__).parent.parent / "common"
+
+L2_DOCS_MAP = {
+    "l2": ("L2 Server (ActivityPub)", L2_DOCS_DIR / "README.md"),
+    "common": ("Common Library", COMMON_DOCS_DIR / "README.md"),
+}
+
+
+@app.get("/help", response_class=HTMLResponse)
+async def help_index(request: Request):
+    """Documentation index page."""
+    username = get_user_from_cookie(request)
+
+    # Build doc links
+    doc_links = ""
+    for key, (title, path) in L2_DOCS_MAP.items():
+        if path.exists():
+            doc_links += f'''
+            <a href="/help/{key}" class="block p-6 bg-dark-600 rounded-lg hover:bg-dark-500 transition-colors">
+                <h2 class="text-xl font-semibold text-white mb-2">{title}</h2>
+                <p class="text-gray-400">View documentation</p>
+            </a>
+            '''
+
+    content = f'''
+    <div class="max-w-4xl mx-auto">
+        <h1 class="text-2xl font-bold text-white mb-6">Documentation</h1>
+        <div class="grid gap-4">
+            {doc_links}
+        </div>
+    </div>
+    '''
+    return HTMLResponse(base_html("Help", content, username))
+
+
+@app.get("/help/{doc_name}", response_class=HTMLResponse)
+async def help_page(doc_name: str, request: Request):
+    """Render a README as HTML."""
+    if doc_name not in L2_DOCS_MAP:
+        raise HTTPException(404, f"Documentation '{doc_name}' not found")
+
+    title, doc_path = L2_DOCS_MAP[doc_name]
+    if not doc_path.exists():
+        raise HTTPException(404, f"Documentation file not found")
+
+    username = get_user_from_cookie(request)
+
+    # Read and render markdown
+    md_content = doc_path.read_text()
+    html_content = markdown.markdown(md_content, extensions=['tables', 'fenced_code'])
+
+    content = f'''
+    <div class="max-w-4xl mx-auto">
+        <div class="mb-4">
+            <a href="/help" class="text-blue-400 hover:underline">&larr; Back to Help</a>
+        </div>
+        <div class="prose prose-invert max-w-none
+                    prose-headings:text-white prose-headings:border-b prose-headings:border-dark-500 prose-headings:pb-2
+                    prose-h1:text-2xl prose-h1:mt-0
+                    prose-h2:text-xl prose-h2:mt-6
+                    prose-a:text-blue-400 hover:prose-a:text-blue-300
+                    prose-pre:bg-dark-600 prose-pre:border prose-pre:border-dark-500
+                    prose-code:bg-dark-600 prose-code:px-1 prose-code:py-0.5 prose-code:rounded prose-code:text-green-300
+                    prose-table:border-collapse
+                    prose-th:bg-dark-600 prose-th:border prose-th:border-dark-500 prose-th:px-4 prose-th:py-2
+                    prose-td:border prose-td:border-dark-500 prose-td:px-4 prose-td:py-2">
+            {html_content}
+        </div>
+    </div>
+    '''
+    return HTMLResponse(base_html(title, content, username))
+
+
 if __name__ == "__main__":
     import uvicorn
     uvicorn.run("server:app", host="0.0.0.0", port=8200, workers=4)