feat: replace CreateHTTPRequest with CreateHTTPRequestScriptVM

Allows the game client to make HTTP API calls from a listen server
(local lobby) instead of requiring a Steam dedicated server.
CreateHTTPRequestScriptVM has the exact same API signature but works
in both dedicated server and listen server contexts.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/vscripts/contracts_manager.lua

@@ -203,7 +203,7 @@ function ContractsManager.prototype.grantOneContract(self, playerId, minTier)
     if not steamId then
         return
     end
-    local req = CreateHTTPRequest(
+    local req = CreateHTTPRequestScriptVM(
         "POST",
         ((SERVER_CONFIG.API_URL .. "/player/") .. tostring(steamId)) .. "/contracts/grant"
     )
@@ -228,7 +228,7 @@ function ContractsManager.prototype.loadContractsFromServer(self, playerId, sync
         end
         return
     end
-    local request = CreateHTTPRequest(
+    local request = CreateHTTPRequestScriptVM(
         "GET",
         ((SERVER_CONFIG.API_URL .. "/player/") .. tostring(steamId)) .. "/contracts"
     )
@@ -261,7 +261,7 @@ function ContractsManager.prototype.persistContractsToServer(self, playerId)
         return
     end
     local list = self.contractsByPlayer:get(playerId) or ({})
-    local request = CreateHTTPRequest(
+    local request = CreateHTTPRequestScriptVM(
         "PUT",
         ((SERVER_CONFIG.API_URL .. "/player/") .. tostring(steamId)) .. "/contracts"
     )