Feature: `/bottlexp` command

## Feature: `/bottlexp` command

### Description
Lets players convert a portion of their XP into Bottles o’ Enchanting.

### Use case
- Share XP with other players
- Store XP safely

### Suggestion
- Command: `/bottlexp <amount>`
- Unlock with 16 bottles via `/boutique`
- Cost: Glass bottles + small XP tax
- Permission: `frenchdiscord.bottlexp`

### Status
🔴 Not started