Add two standalone X11 games (not DWM plugins) for the Nokia 8110 keypad:
- src/games/snake.cpp: Nokia Snake II-style game, 240x296, built-in 5x7 font
- src/games/tetris.cpp: Tetris with next-piece preview, levels, line clears
Both float as dialog windows in dwm, use a self-contained bitmap font (no
font-file dependency), and are controlled via the numeric keypad (2/4/6/8
directions, 5 action) with arrow-key fallbacks.
- scripts/build-games.sh: Docker armv7 cross-compile (mirrors build-sxmo-x11.sh)
- overlay/rootfs/usr/share/sxmo/default_hooks/sxmo_hook_games.sh: Games menu hook
- overlay/rootfs/usr/bin/sxmo_appmenu.sh: add 'Games' entry after 'Apps' and a
games submenu case
Binaries committed to prebuilt/games and overlay/rootfs/usr/bin per repo
convention. Deployed and verified on the live device (window maps, dwm focuses
it, keypad input reaches the game).
The previous commit disabled sxmo_idle.sh and the idle_locker in the
unlock/lock hooks, leaving the display backlight pinned at maximum
brightness forever (Xorg runs with -s 0 -dpms and /sys/power/state is
empty, so the panel never blanks). On a phone with no suspend this is by
far the dominant battery drain.
Restore sxmo_idle.sh and start idle_locker from the unlock and lock hooks
so the screen blanks after SXMO_UNLOCK_IDLE_TIME (default 30s) / once
locked after SXMO_LOCK_IDLE_TIME (default 8s). Locking itself stays
explicit-only, matching the documented design; only the display blanks.
Verified live on the device: after the idle timeout the state transitions
to screenoff and /sys/class/backlight/backlight/brightness drops to 0.