Add interactive task lists and table insertion to markdown editor

- Enable task list checkbox toggling in preview mode with live content updates
- Add task list and table insertion buttons to InsertToolbar
- Implement smart block snippet insertion with automatic newline handling
- Add horizontal scroll wrapper for wide tables in preview
- Fix editor scroll position preservation during content updates
- Use useLayoutEffect to prevent scroll jumps when textarea auto-resizes
- Update task list styling

src/components/PrintView.tsx

@@ -289,6 +289,28 @@ export function PrintView({ jobId }: PrintViewProps) {
               color: #334155;
             }
 
+            .print-note ul:has(> li > input[type="checkbox"]) {
+              list-style: none;
+              padding-left: 0;
+            }
+
+            .print-note li:has(> input[type="checkbox"]) {
+              list-style: none;
+              display: flex;
+              align-items: flex-start;
+              gap: 0.55em;
+              padding-left: 0;
+            }
+
+            .print-note li:has(> input[type="checkbox"])::marker {
+              content: '';
+            }
+
+            .print-note li > input[type="checkbox"] {
+              flex-shrink: 0;
+              margin: 0.3em 0 0;
+            }
+
             .print-note blockquote {
               margin: 1.15em 0;
               padding-left: 1em;