Auto-attack: bow shots chain at full speed, arts start by their cooldown; hang watchdog

- The shot end's button check (0x4def52) answers "held" for the auto-attack
  target, like the melee swing end.
- An art order counts as started when the art's cooldown rises, so bow arts
  and arts ordered mid-swing hand over to auto-attack.
- re/crash.cpp: a watchdog writes sacred_re_hang.dmp when the engine tick
  stops for 10 s while the game is in front.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/game/engine/orders.h

@@ -70,13 +70,15 @@ constexpr size_t kCreatureY = 0x20;
 // +0x150: low word the current action, high word its phase; 0x10000 when
 // standing idle. Measured on the hero: 1 walking (also up to a target),
 // 3 weapon attack, 4 casting a spell (2026-10-16), 6 dying, 8 an art seen
-// after walking up (2026-10-15, presumably a combat move).
+// after walking up (2026-10-15, presumably a combat move), 5 a shot with a
+// projectile weapon (bow, 2026-10-18).
 constexpr size_t kCreatureAction = 0x150;
 enum CreatureAction : int32_t {
     kActionIdle = 0,
     kActionWalk = 1,
     kActionAttack = 3,
     kActionCastSpell = 4,
+    kActionShoot = 5,
     kActionDying = 6,
     kActionCombatMove = 8,
 };