Redesign session selector with multi-line layout

- Custom SessionList component with 2 lines per item
- First line: message text (bold when selected)
- Second line: metadata (time · message count) in dim
- Blue › cursor for selected item
- Added "Resume Session" header
- Handle Ctrl+C (‹x03›) in SelectList for consistency
- Improved date formatting (38 minutes ago, 8 hours ago, etc.)

packages/tui/src/components/select-list.ts

@@ -148,8 +148,8 @@ export class SelectList implements Component {
 				this.onSelect(selectedItem);
 			}
 		}
-		// Escape
-		else if (keyData === "\x1b") {
+		// Escape or Ctrl+C
+		else if (keyData === "\x1b" || keyData === "\x03") {
 			if (this.onCancel) {
 				this.onCancel();
 			}