Add recentCombatants system

Makes the pvp center calculations ignore pvpers that aren't getting kills, etc
Was just noticing that centers weren't following the actual pvp, this should help with that

Author: StrawWagen

lua/cfc_random_spawn/module/sv_player_spawning.lua

@@ -13,13 +13,21 @@ local CLOSENESS_LIMIT = CFCRandomSpawn.Config.CLOSENESS_LIMIT ^ 2
 local CENTER_UPDATE_INTERVAL = customSpawnConfigForMap.centerUpdateInterval or CFCRandomSpawn.Config.CENTER_UPDATE_INTERVAL
 local IGNORE_BUILDERS = CFCRandomSpawn.Config.IGNORE_BUILDERS
 
+local ACTIVE_PLAYER_TIMEOUT = 120 -- players who haven't died/killed anyone in this many seconds aren't 'pvping' and won't influence the pvp center, etc
+
 local DYNAMIC_CENTER_MINSIZE = 2000 -- getDynamicPvpCenter starts at this radius
 local DYNAMIC_CENTER_MAXSIZE = 4000 -- no bigger than this radius
 local DYNAMIC_CENTER_MINSPAWNS = 10 -- getDynamicPvpCenter needs at least this many spawns inside the radius
 local DYNAMIC_CENTER_MAXSPAWNS = 35 -- max possible spawns
 local DYNAMIC_CENTER_SPAWNCOUNTMATCHPVPERS = true -- pvp center gets bigger when more people are pvping
 local DYNAMIC_CENTER_IMPERFECT = true -- throw a bit of randomness in, makes pvp less stiff.
 
+CFCRandomSpawn.recentCombatants = CFCRandomSpawn.recentCombatants or {}
+local recentCombatants = CFCRandomSpawn.recentCombatants
+
+local CurTime = CurTime
+local Vector = Vector
+
 local function defaultPvpCenter()
     return pvpCenters[1]
 end
@@ -79,15 +87,36 @@ local function getMeasurablePlayers()
     local measurablePlayers = {}
     local humans = IGNORE_BUILDERS and getPvpers() or player.GetAll()
 
+    local cur = CurTime()
+
     for _, ply in pairs( humans ) do
-        if ply:Alive() then
+        if ply:Alive() and recentCombatants[ply] > cur then
             table.insert( measurablePlayers, ply )
         end
     end
 
     return measurablePlayers
 end
 
+local function countAsCombatting( ply )
+    local cur = CurTime()
+    recentCombatants[ply] = cur + ACTIVE_PLAYER_TIMEOUT
+end
+
+hook.Add( "PlayerInitialSpawn", "cfc_randomspawn_firstspawn", function( ply )
+    recentCombatants[ply] = 0
+end )
+
+hook.Add( "PlayerDeath", "cfc_randomspawn_trackrecentcombatants", function( died, _inflictor, attacker )
+    if not attacker:IsPlayer() then return end
+    countAsCombatting( died )
+    countAsCombatting( attacker )
+end )
+
+hook.Add( "PlayerDisconnected", "cfc_randomspawn_cleanuprecentcombatants", function( ply )
+    recentCombatants[ply] = nil
+end )
+
 local function getLivingPlayers()
     local livingPlayers = {}
     local humans = player.GetAll()
@@ -196,7 +225,7 @@ end
 local function getPlyAvg( plys, centerPos )
     if not plys or not plys[1] then return centerPos or Vector() end
 
-    local avgSum = Vector()
+    local avgSum = Vector( 0, 0, 0 )
 
     for _, ply in ipairs( plys ) do
         avgSum = avgSum + ply:GetPos()