ItemSyncFixes

Item Sync Fixes is my attempt to fix 3 specific Vintage Story inventory desync symptoms. It is intentionally narrow: it does not try to rewrite inventory networking or make the client authoritative.

The three targeted symptoms are:

1. Crafting output ghost items from partial output moves
2. Rapid clicking or dragging through crafting grid and cursor interactions can make items feel like they move late, flicker backward, or briefly show stale intermediate states.
3. Moving stacks in hotbar/backpack slots can receive exact delayed server self confirmations after the client has already predicted the same final state, causing visible snapback/flicker.