fix v1.31.2: merge/split room pick highlight visible again

- .room.picked moved after .room.outlined: equal specificity, source
  order silently killed the amber highlight in markup (gotcha x4,
  documented inline)
- smoke_merge_highlight.mjs (waits out the 0.12s transition before
  reading computed colors); TESTING/CHANGELOG same-commit

package.json

@@ -1,6 +1,6 @@
 {
   "name": "houseplan-card",
-  "version": "1.31.1",
+  "version": "1.31.2",
   "description": "Interactive house plan Lovelace card for Home Assistant",
   "license": "MIT",
   "type": "module",