feat(vagrant): Tab-Toggle inventory panel + right-click context menu

- lib-core.panel and lib-core.inventory-list-display added to deps (v0.1.0 each)
- backpack-widget created in M.init with label-resolver returning "Rock"
- Drop action registered: removes from backpack, relocates to player position,
  re-registers pickup trigger
- Inspect action registered: prints reg_id via engine.print
- M.update: panel.update(dt) + is_pausing() early-return added after
  quit_to_launcher check
- interaction.update wrapped in panel.is_open() guard to block world triggers
  while panel is visible
- M.draw: panel.render() added at z-top after CI traces
- Q-drop (LIFO quick-drop via Q key) unchanged and parallel to panel Drop action

manifest.module

@@ -1,6 +1,6 @@
 {
     "id": "vagrant-skeleton",
-    "version": "0.8.0",
+    "version": "0.9.0",
     "kind": "module",
     "api": "^0.1",
     "ci_frames": 60,
@@ -17,6 +17,8 @@
         {"id": "lib-core.render",                 "version": "0.2.0"},
         {"id": "lib-core.composition",            "version": "0.2.0"},
         {"id": "lib-core.actor",                  "version": "0.1.0"},
+        {"id": "lib-core.panel",                  "version": "0.1.0"},
+        {"id": "lib-core.inventory-list-display", "version": "0.1.0"},
         {"id": "lib-core.maps","version":"0.5.7"},
         {"id": "lib-core.puppet",                 "version": "0.5.0"},
         {"id": "lib-core.interaction",            "version": "0.1.0"},