[BUG] `Player` is memory leaked if `Fire` is called after `PlayerRemoving`

[dev-alastair]

Describe the bug

After the PlayerRemoving event fires for a player, if any calls are made to Fire or another dispatcher, zap adds that Player to player_map again on the server. This is then never cleaned up and persists forever.

Reproduction

event Test = {
    from: Server,
    type: Reliable,
    call: ManyAsync,
    data: (),
}

Playground link

local Players = game:GetService("Players")
local network = require("./network/server")

Players.PlayerRemoving:Connect(function(player)
	task.wait(5)
	network.Test.Fire(player)
	print("Player will remain in player_map forever!")
end)

Expected behavior

Although this event has been fired in error (after player has left), zap should protect against this or issue a warning when this occurs. As it stands, an event firing seconds after the player leaves silently causes a memory leak.