major refactor of Client and Server

this refactor includes changes to TClient:

- all member fields are now public, but protected with Sync (an alias
  for boost::synchronized_value
- removed all (now) obsolete getters and setters

changes to TServer and TNetwork:

- thread-safe ID generation, previously it was possible for there to be
  ID duplicates. this is now solved by moving id generation and
  assignment into the same mutex locked context.
- deprecated ForEachClientWeak and replaced some usages of it with
  ForEachClient, getting rid of the weak_ptr shit in most places
- implemented a bunch of new functions for getting rid of more weak_ptr
  everywhere

include/TServer.h

@@ -22,14 +22,19 @@ public:
 
     void InsertClient(const std::shared_ptr<TClient>& Ptr);
     void RemoveClient(const std::weak_ptr<TClient>&);
+    void RemoveClient(TClient&);
     // in Fn, return true to continue, return false to break
-    void ForEachClient(const std::function<bool(std::weak_ptr<TClient>)>& Fn);
+    [[deprecated("Use ForEachClient instead")]] void ForEachClientWeak(const std::function<bool(std::weak_ptr<TClient>)>& Fn);
+    void ForEachClient(const std::function<bool(const std::shared_ptr<TClient>&)> Fn);
     size_t ClientCount() const;
 
     void GlobalParser(const std::weak_ptr<TClient>& Client, std::vector<uint8_t>&& Packet, TPPSMonitor& PPSMonitor, TNetwork& Network);
     static void HandleEvent(TClient& c, const std::string& Data);
     RWMutex& GetClientMutex() const { return mClientsMutex; }
 
+    // thread-safe ID lookup & claim
+    void ClaimFreeIDFor(TClient& Client);
+
     const TScopedTimer UptimeTimer;
 
     // asio io context