N°8641 - Dashboard editor front-end first commit for Form SDK integration.

* No dashlet edition
* Dashboard are not persisted
* Unable to load a dashboard from an endpoint (refresh)
* Grid library need proper npm integration

node_modules/gridstack/dist/angular/lib/base-widget.d.ts

@@ -0,0 +1,55 @@
+import { NgCompInputs, NgGridStackWidget } from './types';
+import * as i0 from "@angular/core";
+/**
+ * Base widget class for GridStack Angular integration.
+ */
+export declare abstract class BaseWidget {
+    /**
+     * Complete widget definition including position, size, and Angular-specific data.
+     * Populated automatically when the widget is loaded or saved.
+     */
+    widgetItem?: NgGridStackWidget;
+    /**
+     * Override this method to return serializable data for this widget.
+     *
+     * Return an object with properties that map to your component's @Input() fields.
+     * The selector is handled automatically, so only include component-specific data.
+     *
+     * @returns Object containing serializable component data
+     *
+     * @example
+     * ```typescript
+     * serialize() {
+     *   return {
+     *     title: this.title,
+     *     value: this.value,
+     *     settings: this.settings
+     *   };
+     * }
+     * ```
+     */
+    serialize(): NgCompInputs | undefined;
+    /**
+     * Override this method to handle widget restoration from saved data.
+     *
+     * Use this for complex initialization that goes beyond simple @Input() mapping.
+     * The default implementation automatically assigns input data to component properties.
+     *
+     * @param w The saved widget data including input properties
+     *
+     * @example
+     * ```typescript
+     * deserialize(w: NgGridStackWidget) {
+     *   super.deserialize(w); // Call parent for basic setup
+     *
+     *   // Custom initialization logic
+     *   if (w.input?.complexData) {
+     *     this.processComplexData(w.input.complexData);
+     *   }
+     * }
+     * ```
+     */
+    deserialize(w: NgGridStackWidget): void;
+    static ɵfac: i0.ɵɵFactoryDeclaration<BaseWidget, never>;
+    static ɵprov: i0.ɵɵInjectableDeclaration<BaseWidget>;
+}