Font: add missing bitmap glyphs (/ # * + =) to both Snake and Tetris so
control labels like '4/6 MOVE' and '# PAUSE' render correctly. Also hoist
XSetForeground out of the per-pixel loop in draw_text (both games).
Snake: remove the wall-collision death; the head now wraps through the
opposite edge ((hx+COLS)%COLS, (hy+ROWS)%ROWS). Base speed raised from
70->100 px/sec (~128ms -> ~90ms per step) so it feels less laggy; the
+1 px/sec per 5 food progressive difficulty is unchanged.