feat v1.33.0: background editor — visual decor layer

- third mode tab: draw lines/rects/ovals/text with grid snap, drag
  preview; select+move (Delete key), erase, color/width/fill controls;
  Esc ladder; text dialog with S/M/L sizes and dblclick re-edit
- decor renders under rooms, visible in every mode, click-transparent
  outside its editor; stored in space.decor with backend schema
  (line/rect/ellipse/text variants), rev/optimistic locking as usual
- smoke_decor.mjs (19 checks); smoke_editor_tabs updated to 3 tabs;
  TESTING/CHANGELOG/UX-MODES same-commit

custom_components/houseplan/manifest.json

@@ -16,5 +16,5 @@
   "issue_tracker": "https://github.com/Matysh/houseplan-card/issues",
   "requirements": [],
   "single_config_entry": true,
-  "version": "1.32.1"
+  "version": "1.33.0"
 }