Tetris+

Four Tetris modes in your terminal, each one keeping its own persistent
arcade leaderboard.

Modes

• Marathon -- endless. Survive and score.
• Sprint -- clear 40 lines as fast as you can, and it is ranked by time

rather than by score.

• Ultra -- two minutes on the clock. Score as much as you can.
• Expert -- endless, but starts at level 10, with gravity already open at

170 ms per step instead of 800.

A leaderboard per mode

Every mode keeps its own top-10 table, so a Sprint record can never be
unseated by a Marathon score. Time-ranked boards show a TIME column where the
others show SCORE. Entries take three-letter initials, arcade style, and
survive between sessions. A Sprint time is only recorded if you actually clear
all 40 lines -- bailing out at 30 does not post an unbeatable short time.

Also included: a ghost piece marking where a hard drop will land, a
next-piece preview, pause, and a menu you can drop back to mid-game.

Single file C, no build system, and no dependencies beyond libncurses. Built
for a terminal of at least 50x22; anything smaller gets a polite "terminal too
small" notice instead of a screen full of garbage.