feat: Add WYSIWYG editor components and utilities

- Implemented WysiwygModalManager for managing modals related to code blocks and block settings.
- Created WysiwygSelection for handling text selection across Shadow DOM boundaries.
- Introduced WysiwygShortcuts for managing keyboard shortcuts and slash menu items.
- Developed wysiwygStyles for consistent styling of the WYSIWYG editor.
- Defined types for blocks, slash menu items, and shortcut patterns in wysiwyg.types.ts.

ts_web/elements/dees-input-wysiwyg/blocks/block.base.ts

@@ -0,0 +1,44 @@
+import type { IBlock } from '../wysiwyg.types.js';
+import type { IBlockEventHandlers } from '../wysiwyg.interfaces.js';
+
+// Re-export types from the interfaces
+export type { IBlockEventHandlers } from '../wysiwyg.interfaces.js';
+
+export interface IBlockContext {
+  shadowRoot: ShadowRoot;
+  component: any; // Reference to the wysiwyg-block component
+}
+
+export interface IBlockHandler {
+  type: string;
+  render(block: IBlock, isSelected: boolean): string;
+  setup(element: HTMLElement, block: IBlock, handlers: IBlockEventHandlers): void;
+  getStyles(): string;
+  getPlaceholder?(): string;
+  
+  // Optional methods for editable blocks - now with context
+  getContent?(element: HTMLElement, context?: IBlockContext): string;
+  setContent?(element: HTMLElement, content: string, context?: IBlockContext): void;
+  getCursorPosition?(element: HTMLElement, context?: IBlockContext): number | null;
+  setCursorToStart?(element: HTMLElement, context?: IBlockContext): void;
+  setCursorToEnd?(element: HTMLElement, context?: IBlockContext): void;
+  focus?(element: HTMLElement, context?: IBlockContext): void;
+  focusWithCursor?(element: HTMLElement, position: 'start' | 'end' | number, context?: IBlockContext): void;
+  getSplitContent?(element: HTMLElement, context?: IBlockContext): { before: string; after: string } | null;
+}
+
+
+export abstract class BaseBlockHandler implements IBlockHandler {
+  abstract type: string;
+  abstract render(block: IBlock, isSelected: boolean): string;
+  
+  // Default implementation for common setup
+  setup(element: HTMLElement, block: IBlock, handlers: IBlockEventHandlers): void {
+    // Common setup logic
+  }
+  
+  // Common styles can be defined here
+  getStyles(): string {
+    return '';
+  }
+}