fix+feat: button overrun, natural weapon rolls, Wraith Teeth & Claw (v1.6.1)

CSS: morph-shift-btn now flex: 0 0 auto; max-width: 110px
     specialty-name gets flex: 1; min-width: 0 so it takes remaining space
     flex-wrap on specialty-name-row prevents overflow

Natural weapons:
- template.json: isNaturalWeapon/naturalWeaponDamage/AP/ROF fields on specialty
- Morphic Strike: ROF 2, isNaturalWeapon: true
- Wraith Teeth & Claw added to wraithraider racial abilities (DMG 2, AP 1, ROF 2)
- _ensureRacialAbilities patches existing items with missing natural weapon fields
- _onNaturalWeaponRoll: STR + Melee roll through full weapon chat card pipeline
- STRIKE button appears on any specialty with isNaturalWeapon: true
- All condition/drug/armor/racial mods applied to natural weapon rolls

system.json

@@ -2,7 +2,7 @@
   "id": "zero-engine",
   "title": "Zero Engine (SLA Industries)",
   "description": "A basic game system for SLA Industries using the Zero Engine rules.",
-  "version": "1.6.0",
+  "version": "1.6.1",
   "compatibility": {
     "minimum": 13,
     "verified": "14.359"