Simple Backpack Add-on Rebuilt! (compatible with other addons)

## v1.1.0 — Big update!

### ✨ New
- **Achievement-friendly!** The add-on no longer disables achievements in your world — you can now earn achievements while using the backpack (requires a fresh world created with the add-on enabled).

### 🐷 Piglin behavior
- Removed 7 invalid spear items from the piglin override that were spamming the content log with "Item is invalid" errors — the log is now clean.
- Re-synced the vanilla piglin snapshot to the newest data-driven game version (format 1.26.20).
- Piglins no longer turn hostile when you open a container — opening your backpack won't aggro them anymore.

### 🎒 Backpack improvements
- Rewritten the backpack script for reliable multiplayer: backpacks remember their owner, and pick-up / take-off / destroy actions now target the exact player who interacted instead of guessing the nearest player.
- Removed the old /function command dependency — the add-on works in worlds with cheats disabled, on servers and Realms.

### 🛠️ Compatibility
- Updated and tested for current Minecraft versions (engine 1.26.30+, tested on 1.26.40).

> **Note:** As with any behavior pack, the achievement-friendly mode applies to worlds created with this version of the add-on enabled. Worlds created with older versions keep their existing setting.

(i realized we dont need beta api lol im so dumb)