c671e0b0e3
Adds TR_SAMPLE_BOTS env var support to point to external sample bots (Walls, Fire, SpinBot, etc). Updates test_bullet_economy.nim to use Walls from the sample-bots directory instead of custom WallsBot, removing the hardcoded path dependency. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>