feat: introduce identity-backed goat

docs/SIMULATION_DEFINITIONS.md

@@ -19,13 +19,13 @@ Each executable action definition contains:
 - display name;
 - default duration;
 - optional preferred profession ID;
-- target type: resource, activity, or free movement;
+- target type: resource, activity, animal, or free movement;
 - resource action ID when the action targets a ResourceNode;
 - optional completion-cost resource ID and amount.
 
-The current actions are gather food, gather wood, deposit food, deposit wood,
-withdraw food, patrol, study, eat, rest, sleep, and wander. Idle and dead are
-stable state sentinels, not executable action definitions.
+The current actions are gather food, gather wood, feed animal, deposit food,
+deposit wood, withdraw food, patrol, study, eat, rest, sleep, and wander. Idle
+and dead are stable state sentinels, not executable action definitions.
 
 SimNPC reads default duration and preferred-profession metadata from these
 definitions. WorldViewManager reads target type and resource-action metadata
@@ -33,6 +33,11 @@ instead of maintaining a separate gather-action map. ActionSelectionSystem and
 SimulationManager share the same completion-cost metadata, so patrol and study
 both require one stored wood without duplicating that rule.
 
+`feed_animal` is the first animal-targeted action. Its definition prefers the
+farmer profession and declares an exact one-food completion cost. Selection,
+animal target reservation, and completion remain separate; NPC and player
+completion both use `AnimalCareSystem`'s same pantry-to-animal transaction.
+
 ## Current profession contract
 
 Each profession definition contains a stable `profession_id`, display name,