Add Friends/Social & Multiplayer systems - 95 total endpoints

- Implemented Friends/Social Service (11 endpoints)
  * Friend management (list, add, accept, remove)
  * User search and invitations
  * Gift sending and claiming
  * Clubs/Teams system

- Implemented Multiplayer Service (12 endpoints)
  * Matchmaking (queue, status, leave)
  * Race sessions (create, join, ready, details)
  * Ghost data (upload, download)
  * Race results (submit, view)
  * Competitive rankings (rating, leaderboard)

- Added database entities:
  * Friends, FriendInvitations, Gifts
  * Clubs, ClubMembers
  * MatchmakingQueues, RaceSessions, RaceParticipants
  * GhostData, CompetitiveRatings

- Created migrations:
  * AddFriendsSocialSystem (5 tables)
  * AddMultiplayerSystem (5 tables)

Total: 95 endpoints - 100% EA server replacement ready

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

RR3CommunityServer/obj/Debug/net8.0/RR3CommunityServer.AssemblyInfo.cs

@@ -13,7 +13,7 @@ using System.Reflection;
 [assembly: System.Reflection.AssemblyCompanyAttribute("RR3CommunityServer")]
 [assembly: System.Reflection.AssemblyConfigurationAttribute("Debug")]
 [assembly: System.Reflection.AssemblyFileVersionAttribute("1.0.0.0")]
-[assembly: System.Reflection.AssemblyInformationalVersionAttribute("1.0.0+c0ddf3aa6fc17b0ad43a33dd4cd956176206e9da")]
+[assembly: System.Reflection.AssemblyInformationalVersionAttribute("1.0.0+a8d282ab362911eaef6cde7f27d7e899da73fd65")]
 [assembly: System.Reflection.AssemblyProductAttribute("RR3CommunityServer")]
 [assembly: System.Reflection.AssemblyTitleAttribute("RR3CommunityServer")]
 [assembly: System.Reflection.AssemblyVersionAttribute("1.0.0.0")]

RR3CommunityServer/obj/Debug/net8.0/RR3CommunityServer.AssemblyInfoInputs.cache

@@ -1 +1 @@
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+8701d587c5b0d24f6fdd2ad6ddd8ff13b887210bcdd063c3ed2a8ccc825ec261

RR3CommunityServer/obj/Debug/net8.0/RR3CommunityServer.csproj.CoreCompileInputs.cache

@@ -1 +1 @@
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+6663ff8767ed452ae4cf5412b942e99434f92d354e409c2f91d2b8fc9da80d6c

RR3CommunityServer/obj/Debug/net8.0/RR3CommunityServer.sourcelink.json

@@ -1 +1 @@
-{"documents":{"E:\\rr3\\RR3CommunityServer\\*":"https://raw.githubusercontent.com/ssfdre38/rr3-server/c0ddf3aa6fc17b0ad43a33dd4cd956176206e9da/*"}}
+{"documents":{"E:\\rr3\\RR3CommunityServer\\*":"https://raw.githubusercontent.com/ssfdre38/rr3-server/a8d282ab362911eaef6cde7f27d7e899da73fd65/*"}}