feat: add table cell background color picker

- Extended TableCell and TableHeader to support backgroundColor attribute
- Created TableBackgroundColor component with 21 color options
- Integrated color picker into table cell menu using Mantine UI
- Added support for both regular cells and header cells
- Updated imports to use custom TableHeader from @docmost/editor-ext

apps/server/src/collaboration/collaboration.util.ts

@@ -11,7 +11,6 @@ import { TextStyle } from '@tiptap/extension-text-style';
 import { Color } from '@tiptap/extension-color';
 import { Youtube } from '@tiptap/extension-youtube';
 import Table from '@tiptap/extension-table';
-import TableHeader from '@tiptap/extension-table-header';
 import {
   Callout,
   Comment,
@@ -22,6 +21,7 @@ import {
   LinkExtension,
   MathBlock,
   MathInline,
+  TableHeader,
   TableCell,
   TableRow,
   TiptapImage,
@@ -31,7 +31,7 @@ import {
   Drawio,
   Excalidraw,
   Embed,
-  Mention
+  Mention,
 } from '@docmost/editor-ext';
 import { generateText, getSchema, JSONContent } from '@tiptap/core';
 import { generateHTML } from '../common/helpers/prosemirror/html';
@@ -46,7 +46,7 @@ export const tiptapExtensions = [
     codeBlock: false,
   }),
   Comment,
-  TextAlign.configure({ types: ["heading", "paragraph"] }),
+  TextAlign.configure({ types: ['heading', 'paragraph'] }),
   TaskList,
   TaskItem,
   Underline,
@@ -64,9 +64,9 @@ export const tiptapExtensions = [
   DetailsContent,
   DetailsSummary,
   Table,
-  TableHeader,
-  TableRow,
   TableCell,
+  TableRow,
+  TableHeader,
   Youtube,
   TiptapImage,
   TiptapVideo,
@@ -76,7 +76,7 @@ export const tiptapExtensions = [
   Drawio,
   Excalidraw,
   Embed,
-  Mention
+  Mention,
 ] as any;
 
 export function jsonToHtml(tiptapJson: any) {