Applied as-is. The client precheck for withdrawing a board operator onto an occupied hand slot now treats that operator's own hand summon stack as a free slot, which the server already accepted. Temp stacks, board summons, another player's tokens, and an item that only carries ownerUid stay HAND_FULL. stack.count is not extra slots. Dropping on a chess still checks the swap first.
Tests: node --test test/ui/gameLogic.test.js test/ui/facing.test.js test/ui/uiFixes.test.js test/match/feedback1-placement.test.js test/match/feedback5-we2-placement.test.js — 116 pass, 0 fail. Before this commit: npm run -s lint — 0 errors (134 existing warnings); npm run -s typecheck — pass; npm run -s check:imports — pass; node --test test/docs-consistency.test.js test/docs-paths.test.js test/version.test.js test/package.test.js — 47 pass, 0 fail. No new UI strings, so the i18n check was not run. No golden update.