Complete M11 Creator Studio and M12 Trust & Safety for PC5

- Creator Studio: Visual behavior & property inspector, GLB model importer, binary persistence
- Trust & Safety: 18+ TOS confirmation (DOB removed), creator guidelines & briefing card on join, in-game reporting HUD
- Test Harness: Add --filter, --skip-backend, --skip-godot to run_checkpoint_tests.py

scripts/discovery_api_client.gd

@@ -12,6 +12,7 @@ class WorldSummary extends RefCounted:
 	var tags: Array = []
 	var play_count: int = 0
 	var created_at: String = ""
+	var content_guidelines: String = ""
 	var owner_id: int = 0
 	var owner_username: String = ""
 
@@ -21,6 +22,7 @@ class WorldSummary extends RefCounted:
 		w.name = str(d.get("name", ""))
 		w.description = str(d.get("description", "")) if d.get("description") != null else ""
 		w.category = str(d.get("category", "")) if d.get("category") != null else ""
+		w.content_guidelines = str(d.get("content_guidelines", "")) if d.get("content_guidelines") != null else ""
 		var raw_tags = d.get("tags", [])
 		w.tags = raw_tags if raw_tags is Array else []
 		w.play_count = int(d.get("play_count", 0))
@@ -31,6 +33,7 @@ class WorldSummary extends RefCounted:
 		return w
 
 
+
 class DiscoveryResult extends RefCounted:
 	var items: Array[WorldSummary] = []
 	var total: int = 0