Game Controller (backgammon-game.js) rewrite:
- Fix selection: click same piece to deselect, click another to swap
- Bar enforcement: must enter from bar first with clear message
- Auto-pass when no moves remain for unused dice
- Bot waiting status message visible during thinking
- Opening roll shows clear "your turn" status with dice values
- Pass button action for truly stuck positions
- Smart move validation with proper die tracking
- Individual bot move logging
- Source validation: only select pieces that have moves

UI (backgammon-ui.js) rewrite:
- setSelected directly applies DOM classes (no render cycle needed)
- Status text system: guides player ("Select piece", "Choose target")
- Movable checkers highlighted with golden ring when it's your turn
- Dice remaining indicator text below dice
- Pass/skip button shown when stuck
- Active player gold border highlight
- Tap feedback animation
- Hover preview on valid targets
- New game button in result overlay
- Valid target points show dashed circle indicator

CSS additions:
- .bg-point--clickable with gold ring on top checker
- .bg-point--hover-preview green tint
- .bg-move-flash animation
- .bg-status, .bg-pass-btn, .bg-dice-remaining styles
- .bg-new-game-btn in overlay
- Valid point dashed circle indicator
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>