feat: add chess resign and undo actions

LOG.md

@@ -2,6 +2,18 @@
 
 ## 2026-06-19
 
+- Added Maia game resign and undo API wrappers, then wired the play screen with in-progress-only "무르기" and "기권" actions plus a persistent "새 게임" link back to the setup screen.
+- Locked board/actions during move, undo, and resign requests, updated the game cache from backend responses as the single source of truth, and refreshed history/stat queries after successful state changes.
+- Added resigned-loss labeling so play, recent games, and history can show `기권패` for `RESIGNED` losses while still grouping them under losses.
+- Validation: `npm run lint` passed and `npm run build` passed. Authenticated browser verification against the live Maia backend was not run in this session.
+- Recommended next task: test resign and undo with an authenticated real game, including black-player games where Maia's opening white move must remain after undo.
+
+- Reworked the shared chess board UI with a bordered board surface, high-contrast chip-style pieces, stronger selected/legal/last-move highlights, and transform-based piece movement transitions so player and Maia moves read as motion instead of instant jumps.
+- Connected the daily puzzle board to the shared `ChessBoard` component, removing duplicated piece rendering and adding drag/drop support for puzzle moves.
+- Updated Maia play state so optimistic player moves are highlighted locally while pending, then Maia's returned move can animate from the server response; changed the pending overlay into a small status pill so it no longer hides the board.
+- Validation: `npm run lint` passed and `npm run build` passed. A local dev server is running on `http://localhost:3124`; browser verification with a temporary local puzzle API confirmed 64 squares, 32 piece-layer nodes, 0.42s piece transition styling, square selection/legal target markers, and no console errors. The temporary API was stopped after verification.
+- Recommended next task: verify `/chess/play/{gameId}` against the real Maia backend with an authenticated account to tune the exact Maia response timing and capture/promotion edge cases.
+
 - Added the authenticated Maia chess frontend: `/chess` lobby with rating/color/model and advanced settings, `/chess/play/[gameId]` playable board with backend FEN synchronization and PGN copy, and `/chess/history` account game history with outcome filters.
 - Extended the chess API client and shared types for Maia game create/list/stats/detail/PGN/move endpoints while leaving the public `/api/chess-puzzles/**` puzzle request unchanged.
 - Updated the Dock/menu/shell route handling so Chess opens the Maia lobby, with the existing public puzzle page still available at `/play/chess`.