Let old saves through the player left guard

on_pre_player_left_game runs before on_server_startup when an old autosave
with connected players is loaded, so the data is still under inventory_sync.
The guard returned before get_script_data() could move it, and the recovery
upload was never sent.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugins/player_sync/module/player_sync.lua

@@ -379,7 +379,8 @@ end
 -- Upload inventory when a player leaves the game. Triggers on restart after crash if player was online during crash.
 player_sync.events[defines.events.on_pre_player_left_game] = function(event)
 	-- for some reason, on_pre_player_left_game gets called before on_server_startup so script_data isn't ready yet
-	if not compat.script_data.player_sync then
+	-- migrate: saves from before the rename still have their data under inventory_sync
+	if not compat.script_data.player_sync and not compat.script_data.inventory_sync then
 		log("ERROR: script data for player sync is not defined")
 		return
 	end