Add lobby plugin with server browser listing

Players connecting through the player proxy are sent to a lobby
instance running their Factorio version, where an in-game list shows
the instances in the cluster. Picking one starts it if needed and moves
the player there with LuaPlayer.connect_to_server once it's running,
while the proxy keeps routing the player to it until they have joined,
covering the second connection Factorio makes to fetch a user key.
Players connecting to the dedicated port of a stopped instance wait in
a lobby while it starts instead of timing out.

The cluster can be listed in the Factorio server browser as one game
per lobby version with the players online in the whole cluster, and
instances with a dedicated proxy port can be listed on their own,
including while stopped. The listed build comes from probing the
instance through the proxy, as the browser only shows games with the
exact version and build of the client.

The controller now creates the player proxy before loading plugins so
they can use it from their entrypoints.

packages/controller/src/Controller.ts

@@ -436,8 +436,7 @@ export default class Controller {
 		this.app.locals.staticRoot = this.config.get("controller.static_url");
 
 		// Load plugins
-		await this.loadPlugins();
-
+		// Created before plugins load so they can use it, but only started after they have attached their hooks
 		const playerProxyPort = this.config.get("controller.player_proxy_port");
 		if (playerProxyPort !== null) {
 			this.playerProxyServer = new PlayerProxyServer(
@@ -445,9 +444,11 @@ export default class Controller {
 				logger.child({ component: "player_proxy" }),
 				playerProxyPort,
 			);
-			await this.playerProxyServer.start();
 		}
 
+		await this.loadPlugins();
+		await this.playerProxyServer?.start();
+
 		// Log all express errors from middleware or routes (app.use is missing the type overload)
 		this.app.use((err: Error, req: express.Request, res: express.Response, next: express.NextFunction): void => {
 			const url = lib.redactUrl(req.originalUrl);