CARD C05 - R8: drop the 14 vestigial TU prototypes of build_game_variant_* (on top of c2_all)
written: 2026-09-26 01:14:23 -0700 (BEFORE the compile)

Observed discrepancy: game_engine.c re-declares 14 of its own public builders (race .. team_king) that
game_engine_playlist.h already declares (rule 16: do not duplicate a shared prototype). Their only in-TU caller,
game_engine_get_variant_by_name, is defined AFTER every builder (J: January emits the builders at 0x985F0..0x99410
and get_variant_by_name at 0x9C570, i.e. source order), so the prototypes are unused forward declarations.
Proposed correction: delete them (no include added: game_engine.c does not need game_engine_playlist.h).
Compiler-state prediction: C1 numbering of every later function drops by ~14 x (1 name + 1 named parameter + 1) =
~-42. From c2_all (+16 over vTU's origin, band 9..13) that is ~-26, outside the known band, but other functions'
bands are unknown.
PREDICTION: 180/180 (low confidence). Stance fixed in advance: keep R8 only if game_engine stays 180/180 (rule 62);
otherwise leave the prototypes and disclose them.
Decisive test: revgate game_engine on c3 = c2_all + R8.
