Add ServerMessageService for broadcasting player state updates, implement PlayerListState model, and update ChatService to synchronize active player states across servers.

open_api/src/main/resources/chat-api.yml

@@ -12,6 +12,40 @@ tags:
     description: Data for displaying Chat messages to clients
 
 paths:
+  /chat/hide:
+    post:
+      tags:
+        - chat
+      summary: Hide the authenticated user from the active player list for this session
+      operationId: hideUserFromPlayerList
+      responses:
+        "204":
+          description: User hidden for the current session
+
+  /chat/show:
+    post:
+      tags:
+        - chat
+      summary: Show the authenticated user in the active player list for this session
+      operationId: showUserInPlayerList
+      responses:
+        "204":
+          description: User shown for the current session
+
+  /chat/visibility:
+    get:
+      tags:
+        - chat
+      summary: Get the authenticated user's active player list visibility
+      operationId: getPlayerListVisibility
+      responses:
+        "200":
+          description: Current visibility mode
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/PlayerListVisibility"
+
   /chat/send/chat/message:
     post:
       tags:
@@ -47,6 +81,14 @@ paths:
           description: Accepted
 components:
   schemas:
+    PlayerListVisibility:
+      type: object
+      required:
+        - hidden
+      properties:
+        hidden:
+          type: boolean
+
     User:
       type: object
       required: