docs: add MCP OAuth documentation and fix lint

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/server/mcp/index.ts

@@ -117,7 +117,8 @@ mcpRoutes.use("/*", async (c, next) => {
 
 	// No auth provided — return 401 with WWW-Authenticate to trigger OAuth flow
 	return c.text("Unauthorized", 401, {
-		"WWW-Authenticate": 'Bearer resource_metadata="/.well-known/oauth-authorization-server"',
+		"WWW-Authenticate":
+			'Bearer resource_metadata="/.well-known/oauth-authorization-server"',
 	});
 });