Remove config groups

Refactor away the config group concept and simplyfy the way config
fields are defined.  Fields are defined directly as properties of the
static field fieldDefinitions on the class itself with a separate
interface to declare the types of fields.

This makes it possible to easily make accessing the config fields type
checked in a way that lets plugins extend the interfaces with their own
config options by adding additional fields to the interface via
declation merging.

packages/controller/src/BaseControllerPlugin.ts

@@ -1,5 +1,5 @@
 import type {
-	CollectorResult, ConfigGroup, Event, InstanceStatus, Logger,
+	CollectorResult, Event, InstanceStatus, Logger,
 	ModPack, ModInfo, PlayerEvent, PluginNodeEnvInfo,
 } from "@clusterio/lib";
 import type Controller from "./Controller";
@@ -99,12 +99,11 @@ export default class BaseControllerPlugin {
 	 * Invoked after the value of the config field given by `field` has
 	 * changed on the controller.
 	 *
-	 * @param group -
-	 *     The group who's field got changed.
 	 * @param field - Name of the field that changed.
+	 * @param curr - The current value of the field.
 	 * @param prev - The previous value of the field.
 	 */
-	async onControllerConfigFieldChanged(group: ConfigGroup, field: string, prev: unknown) { }
+	async onControllerConfigFieldChanged(field: string, curr: unknown, prev: unknown) { }
 
 	/**
 	 * Called when the value of an instance config field changed.
@@ -114,12 +113,11 @@ export default class BaseControllerPlugin {
 	 *
 	 * @param instance -
 	 *     The instance the config changed on.
-	 * @param group -
-	 *     The group who's field got changed.
 	 * @param field - Name of the field that changed.
+	 * @param curr - The current value of the field.
 	 * @param prev - The previous value of the field.
 	 */
-	async onInstanceConfigFieldChanged(instance: InstanceInfo, group: ConfigGroup, field: string, prev: unknown) { }
+	async onInstanceConfigFieldChanged(instance: InstanceInfo, field: string, curr: unknown, prev: unknown) { }
 
 	/**
 	 * Called before collecting Prometheus metrics