Implement prototype: venue-driven simulation core, scenarios, tests, and playable entrance scene

- Godot 4.3 project scaffold with first-person guard, procedural world,
  interaction HUD, access inspection, radio forms, debug overlay, shift review
- Simulation core: ShiftCoordinator, VenueScenario, EventScheduler, NPCController/FSM,
  AccessVerifier, EscalationManager, RadioSystem, IncidentRecorder,
  ReputationEvaluator, CrowdSystem, EventBus
- Three authored scenarios (Hollywood Blvd building, The Joke Shop, TV studio)
- Custom headless test runner (25 tests) replacing editor-dependent GUT,
  plus GitHub Actions CI
- Documentation workflow live: README, PLAN (tech stack), TODO/DONE, MEMORY

src/core/access_artifact.gd

@@ -0,0 +1,22 @@
+class_name AccessArtifact
+extends Resource
+
+const Rules := preload("res://src/core/rules.gd")
+## An item or piece of evidence used to verify entry (PLAN.md: Authorized Access).
+
+@export var kind: int = Rules.AccessKind.NONE
+@export var status: int = Rules.ArtifactStatus.MISSING
+
+## Human-readable attributes the player can inspect, e.g. color, pattern, date,
+## event marking, DOB, name, ticket section. Populated by scenario content.
+@export var attributes: Dictionary = {}
+
+func _init(p_kind: int = Rules.AccessKind.NONE, p_status: int = Rules.ArtifactStatus.MISSING, p_attributes: Dictionary = {}) -> void:
+	kind = p_kind
+	status = p_status
+	attributes = p_attributes
+
+func summary() -> String:
+	var kind_name: String = Rules.ACCESS_KIND_NAMES.get(kind, "None")
+	var status_name: String = Rules.ARTIFACT_STATUS_NAMES.get(status, "Unknown")
+	return "%s (%s)" % [kind_name, status_name]