perf(Root,Portal,Overlay): batch stylesheet writes into one invalidation per commit - #1344

Bugbot Analysis Progress (2m 52s elapsed)

✅ Gathered PR context (5s)
✅ Completed bug detection (2m 47s)
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Final Result: Bugbot completed review - no issues found! ✅

Request ID: serverGenReqId_91fe5791-6909-4e9a-ac1f-dd2b13595781