feat(inline-edit): add WYSIWYG inline dashboard editing mode

Replace the disconnected board edit page with inline editing directly
on the board view. Toggle with Ctrl+E or the Edit button. Features:

- Edit mode store with changeset accumulation and batch save
- Floating toolbar (save, discard, add section, board settings, exit)
- Widget hover overlays with edit/delete/drag controls
- Type-specific widget config panels for all 14 widget types
- Section inline editing (title, icon picker, delete)
- "+" buttons for adding widgets and sections inline
- Section-level drag-and-drop reordering via svelte-dnd-action
- Batch save API endpoint (single Prisma transaction)
- Board properties side panel with live theme/wallpaper preview
- Modal widget type picker with search filtering
- Icon picker component with visual grid and search
- Confirmation dialog modal for all destructive actions
- HTML format support for Note widget (in addition to markdown/text)
- Full i18n support (en + ru) for all new UI strings
- Legacy edit page banner linking to new inline mode

src/lib/utils/validators.ts

@@ -162,7 +162,7 @@ export const bookmarkWidgetConfigSchema = z.object({
 
 export const noteWidgetConfigSchema = z.object({
 	content: z.string().max(10000, 'Content too long'),
-	format: z.enum(['markdown', 'text']).default('markdown')
+	format: z.enum(['markdown', 'text', 'html']).default('markdown')
 });
 
 export const embedWidgetConfigSchema = z.object({