The primaryRadius for 3+ players was 0.10, placing bots ~4 tiles apart on
toroidal grids - outside the attack radius of sqrt(12) ≈ 3.46 tiles.
This caused idle bots to never fight, violating the forcing function.
Reduced primaryRadius to 0.063, which places bots ~3.4 tiles apart
(within attack range). Verified with 3-player idle match: all bots die
in turn 1 due to combat (3 combat_deaths).
Acceptance: 3+ player matches with idle bots now have combat_death
events (bots fight immediately on spawn), matching 2-player behavior.
Closes: bf-k9ov
e8fda06163