Add thread safety for group operations (#1816)

Fixes crashes and race conditions when bots perform group/guild/arena
operations by moving thread-unsafe code to world thread.

Potentially fixes #1124

## Changes

- Added operation queue system that runs in world thread
- Group operations (invite, remove, convert to raid, set leader) now
queued
- Arena formation refactored to use queue
- Guild operations changed to use packet queueing

## Testing

Set `MapUpdate.Threads` > 1 in worldserver.conf to enable multiple map
threads, then test:
- Group formation and disbanding
- Arena team formation
- Guild operations (invite, promote, demote, remove)

- Run with TSAN
cmake ../ \
  -DCMAKE_CXX_FLAGS="-fsanitize=thread -g -O1" \
  -DCMAKE_C_FLAGS="-fsanitize=thread -g -O1" \
  -DCMAKE_EXE_LINKER_FLAGS="-fsanitize=thread" \
  -DCMAKE_INSTALL_PREFIX=/path/to/install \
  -DCMAKE_BUILD_TYPE=RelWithDebInfo

build

export
TSAN_OPTIONS="log_path=tsan_report:halt_on_error=0:second_deadlock_stack=1"
./worldserver

The crashes/race conditions should no longer occur with concurrent map
threads.

## New Files

- `PlayerbotOperation.h` - Base class defining the operation interface
(Execute, IsValid, GetPriority)
- `PlayerbotOperations.h` - Concrete implementations:
GroupInviteOperation, GroupRemoveMemberOperation,
GroupConvertToRaidOperation, GroupSetLeaderOperation,
ArenaGroupFormationOperation
- `PlayerbotWorldThreadProcessor.h/cpp` - Singleton processor with
mutex-protected queue, processes operations in WorldScript::OnUpdate
hook, handles batch processing and validation

---------

Co-authored-by: blinkysc <blinkysc@users.noreply.github.com>
Co-authored-by: SaW <swerkhoven@outlook.com>
Co-authored-by: bash <hermensb@gmail.com>

src/Playerbots.cpp

@@ -25,6 +25,7 @@
 #include "Metric.h"
 #include "PlayerScript.h"
 #include "PlayerbotAIConfig.h"
+#include "PlayerbotWorldThreadProcessor.h"
 #include "RandomPlayerbotMgr.h"
 #include "ScriptMgr.h"
 #include "cs_playerbots.h"
@@ -300,7 +301,8 @@ class PlayerbotsWorldScript : public WorldScript
 {
 public:
     PlayerbotsWorldScript() : WorldScript("PlayerbotsWorldScript", {
-        WORLDHOOK_ON_BEFORE_WORLD_INITIALIZED
+        WORLDHOOK_ON_BEFORE_WORLD_INITIALIZED,
+        WORLDHOOK_ON_UPDATE
     }) {}
 
     void OnBeforeWorldInitialized() override
@@ -329,6 +331,13 @@ public:
 
         LOG_INFO("server.loading", ">> Loaded playerbots config in {} ms", GetMSTimeDiffToNow(oldMSTime));
         LOG_INFO("server.loading", " ");
+        LOG_INFO("server.loading", "Playerbots World Thread Processor initialized");
+    }
+
+    void OnUpdate(uint32 diff) override
+    {
+        sPlayerbotWorldProcessor->Update(diff);
+        sRandomPlayerbotMgr->UpdateAI(diff);  // World thread only
     }
 };
 
@@ -390,8 +399,7 @@ public:
 
     void OnPlayerbotUpdate(uint32 diff) override
     {
-        sRandomPlayerbotMgr->UpdateAI(diff);
-        sRandomPlayerbotMgr->UpdateSessions();
+        sRandomPlayerbotMgr->UpdateSessions();  // Per-bot updates only
     }
 
     void OnPlayerbotUpdateSessions(Player* player) override