Finish the plugin system integration tests

Adds the last three checks from #342 to test_plugin: an InstanceEcho
request handled on a running instance, a Lua module with a remote
interface that the request calls over RCON, and log tagging checks for
the plugin field and host/instance ids on the controller, host and
instance log lines.

test_plugin now has a module, so the create_scenario and patch unit
tests that relied on it having none use global_chat instead.

Closes #342

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

test/file/test_plugin/index.js

@@ -1,7 +1,7 @@
 // Plugin exercising the plugin system in the integration tests, see #342.
 // Written as plain JavaScript so that it does not need to be built.
 
-import { ControllerEcho, HostEcho, HostEchoReceived } from "./messages.js";
+import { ControllerEcho, HostEcho, HostEchoReceived, InstanceEcho } from "./messages.js";
 
 export const plugin = {
 	name: "test_plugin",
@@ -17,5 +17,6 @@ export const plugin = {
 		ControllerEcho,
 		HostEcho,
 		HostEchoReceived,
+		InstanceEcho,
 	],
 };

test/file/test_plugin/instance.js

@@ -1,3 +1,7 @@
+import * as lib from "@clusterio/lib";
+
+import { InstanceEcho } from "./messages.js";
+
 export default async function(context) {
 	const { instance, plugin, logger } = context;
 	logger.info("test_plugin instance loaded");
@@ -5,4 +9,11 @@ export default async function(context) {
 	instance.hooks.start.attach(plugin.name, async () => {
 		logger.info("test_plugin instance started");
 	});
+
+	instance.handle(InstanceEcho, async (request) => {
+		logger.info(`test_plugin instance echo ${request.text}`);
+		const text = lib.escapeString(request.text);
+		const response = await instance.sendRcon(`/sc rcon.print(remote.call("test_plugin", "echo", "${text}"))`);
+		return response.replace(/\n$/, "");
+	});
 }

test/file/test_plugin/messages.js

@@ -54,3 +54,22 @@ export class HostEchoReceived {
 	toJSON() { return this.text; }
 	static fromJSON(json) { return new this(json); }
 }
+
+// Sent from ctl to an instance, which answers with the text echoed back by
+// the remote interface of the plugin's Lua module.
+export class InstanceEcho {
+	static type = "request";
+	static src = "control";
+	static dst = "instance";
+	static plugin = "test_plugin";
+	static permission = null;
+	static Response = JsonString;
+
+	constructor(text) {
+		this.text = text;
+	}
+
+	static jsonSchema = { type: "string" };
+	toJSON() { return this.text; }
+	static fromJSON(json) { return new this(json); }
+}

test/file/test_plugin/module/module.json

@@ -0,0 +1,4 @@
+{
+	"name": "test_plugin",
+	"require": ["test_plugin.lua"]
+}

test/file/test_plugin/module/test_plugin.lua

@@ -0,0 +1,5 @@
+remote.add_interface("test_plugin", {
+	echo = function(text)
+		return text
+	end,
+})