gameplay: allow bots to deal explosive self dmg if non-significant

if it's more than 30% of their HP, then don't do it!
but otherwise, this fixes a bug where bots would freeze
and not do anything if they were too close to their target

Author: mastercoms

src/game/server/tf/bot/behavior/tf_bot_behavior.cpp

@@ -1427,7 +1427,14 @@ void CTFBotMainAction::FireWeaponAtEnemy( CTFBot *me )
 
 					float hitRange = trace.fraction * 1.1f * threatRange;
 
-					if ( hitRange < TF_ROCKET_RADIUS )
+					// Accurate enough base damage
+					float flExplosiveDamage = 100.0f;
+					// Don't factor overheal
+					float flCurrentHealth = MIN( me->GetHealth(), me->GetMaxHealth() );
+					// Don't hit ourselves if the explosion will do a noticeable amount of our health
+					bool bTooMuchSelfDamage = flExplosiveDamage > 0.3f * flCurrentHealth;
+
+					if ( bTooMuchSelfDamage && hitRange < TF_ROCKET_RADIUS )
 					{
 						// shot will impact very near us
 						if ( !trace.m_pEnt || ( trace.m_pEnt && !trace.m_pEnt->MyCombatCharacterPointer() ) )