feat(workspace): mark several notes (Ctrl/Cmd, Shift) and drag them into a folder or onto the trash

Ctrl/Cmd+click toggles, Shift+click marks a range in the order shown; dragging a marked note takes
all marked ones along (no merge then). The trash at the bottom of the sidebar becomes a drop target,
also for a single note and on phones (native long-press drag); a toast offers undo. Escape, a plain
click or a click on empty space clears the marks. v0.37.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/package.json

@@ -1,7 +1,7 @@
 {
   "name": "mindsift-frontend",
   "private": true,
-  "version": "0.36.0",
+  "version": "0.37.0",
   "license": "Unlicense",
   "type": "module",
   "scripts": {