feat(dashboard,admin-sdk,admin-shared,admin-vite-plugin): Add support for UI extensions (#7383)

* intial work

* update lock

* add routes and fix HMR of configs

* cleanup

* rm imports

* rm debug from plugin

* address feedback

* address feedback

packages/admin-next/admin-shared/src/extensions/config/index.ts

@@ -0,0 +1,2 @@
+export * from "./types"
+export * from "./utils"

packages/admin-next/admin-shared/src/extensions/config/types.ts

@@ -0,0 +1,12 @@
+import type { ComponentType } from "react"
+
+import { InjectionZone } from "../widgets"
+
+export type WidgetConfig = {
+  zone: InjectionZone | InjectionZone[]
+}
+
+export type RouteConfig = {
+  label?: string
+  icon?: ComponentType
+}

packages/admin-next/admin-shared/src/extensions/config/utils.ts

@@ -0,0 +1,37 @@
+import { RouteConfig, WidgetConfig } from "./types"
+
+function createConfigHelper<TConfig extends Record<string, unknown>>(
+  config: TConfig
+): TConfig {
+  return {
+    ...config,
+    /**
+     * This property is required to allow the config to be exported,
+     * while still allowing HMR to work correctly.
+     *
+     * It tricks Fast Refresh into thinking that the config is a React component,
+     * which allows it to be updated without a full page reload.
+     */
+    $$typeof: Symbol.for("react.memo"),
+  }
+}
+
+/**
+ * Define a widget configuration.
+ *
+ * @param config The widget configuration.
+ * @returns The widget configuration.
+ */
+export function defineWidgetConfig(config: WidgetConfig) {
+  return createConfigHelper(config)
+}
+
+/**
+ * Define a route configuration.
+ *
+ * @param config The route configuration.
+ * @returns The route configuration.
+ */
+export function defineRouteConfig(config: RouteConfig) {
+  return createConfigHelper(config)
+}