feat: single-page title menu, in-game quickbar and smooth ghosts

fix: harden mode state machine + per-duck randomized chirps

feat: duck-head modal logo, input lockout mid-roll, quieter quack

feat: ZQSD turn keys + wordmark-only welcome modal

feat: modal logo artwork + sync colour variants from pollen site

feat: HUD UX pass - state label with slot-machine roll, keycap hints, per-device highlighting, quack sound from the runtime