feat: replace core homepage widget registry with generic extension points

plugins/host-metrics/src/shared/homepage.ts

@@ -1,4 +1,5 @@
-import type { HomepageWidgetContribution } from "@termix/plugin-sdk/frontend";
+import type { ComponentType, ReactNode } from "react";
+import type { ExtensionContribution } from "@termix/plugin-sdk/frontend";
 
 /** The homepage's grid step, in pixels. */
 export const GRID_SIZE = 30;
@@ -25,7 +26,18 @@ export interface WidgetEditFormProps<C> {
   onChange: (config: C) => void;
 }
 
-export type WidgetDefinition<C> = Omit<
-  HomepageWidgetContribution<C>,
-  "defaultConfig"
-> & { defaultConfig: C };
+/** What app.registerExtension("homepage.widgets", ...) takes. */
+export interface WidgetDefinition<C> extends ExtensionContribution {
+  id: string;
+  name: string;
+  description: string;
+  category: "links" | "info" | "system" | "monitoring";
+  icon: ReactNode;
+  defaultConfig: C;
+  defaultSize: { w: number; h: number };
+  minSize: { w: number; h: number };
+  components: {
+    view: ComponentType<WidgetComponentProps<C>>;
+    editForm?: ComponentType<WidgetEditFormProps<C>>;
+  };
+}