feat(board): add shared physical quest boards

knowledge/log.md

@@ -26,3 +26,10 @@ description: Chronological record of material decisions affecting Spigot Quest B
 - Published the project to the public `dmg/spigot-quest-board` Gitea repository.
 - Added strict Java 25/Purpur 26.2 Gradle builds, plugin metadata, a metadata regression test, and CI/release workflows modeled on Spigot Base.
 - Verified the plugin foundation and JAR with `./gradlew clean check jar`.
+
+## 2026-09-05 — Shared physical quest boards
+
+- Added durable world-UUID and block-coordinate board registration through `/questadmin createboard`.
+- Registered main-hand interactions open one shared native Purpur dialog while unregistered blocks remain untouched.
+- Persistence publishes a board only after an atomic YAML save succeeds and rejects duplicate locations.
+- Verified 11 tests and the plugin JAR with `./gradlew clean check jar`.

knowledge/user-stories/us-002-create-and-use-shared-quest-boards.md

@@ -2,7 +2,7 @@
 type: User Story
 title: "US-002: Create and use shared quest boards"
 description: Let administrators establish persistent physical boards that expose one shared quest system.
-status: backlog
+status: done
 ---
 
 # US-002: Create and use shared quest boards
@@ -11,15 +11,15 @@ As an **administrator**, I want to turn a targeted block into a quest board so t
 
 ## Acceptance criteria
 
-- [ ] An authorized administrator can use `/questadmin createboard` to register the block they are targeting.
-- [ ] Creation rejects a missing, invalid, or already registered target without changing state.
-- [ ] Registered boards persist across server restarts with their world and block coordinates.
-- [ ] Interacting with any registered board opens the quest-board interface.
-- [ ] Every registered board exposes the same global quests and claimable items.
-- [ ] The interface uses Purpur's supported native dialog API and follows the interaction style of Spigot Base.
-- [ ] Ordinary block interaction is not intercepted at unregistered locations.
-- [ ] Administrative actions require the `spigotquestboard.admin` permission, granted to server operators by default.
-- [ ] Automated tests verify board registration, persistence, shared visibility, authorization, and interaction routing.
+- [x] An authorized administrator can use `/questadmin createboard` to register the block they are targeting.
+- [x] Creation rejects a missing, invalid, or already registered target without changing state.
+- [x] Registered boards persist across server restarts with their world and block coordinates.
+- [x] Interacting with any registered board opens the quest-board interface.
+- [x] Every registered board exposes the same global quests and claimable items.
+- [x] The interface uses Purpur's supported native dialog API and follows the interaction style of Spigot Base.
+- [x] Ordinary block interaction is not intercepted at unregistered locations.
+- [x] Administrative actions require the `spigotquestboard.admin` permission, granted to server operators by default.
+- [x] Automated tests verify board registration, persistence, shared visibility, authorization, and interaction routing.
 
 ## Related