Feature: Items are not mailed when inventory is full

### Current Behaviour

When your inventory is full, items are simply shown in the loot window and you get a message saying your inventory is full.

### Expected Behaviour

Items should be mailed to you when your inventory is full

### Steps to reproduce the problem

1. Have full inventory
2. Loot item(s)

### Extra Notes

Since commit [d777d18](https://github.com/azerothcore/mod-aoe-loot/commit/d777d183c521201c46a68dd1ecf431cbc21317bc)

### AC rev. hash/commit

https://github.com/azerothcore/azerothcore-wotlk/commit/bf17d93727e1

### Operating system

Ubuntu 22.04.3 LTS (x64)

### Custom changes or Modules

- mod-account-achievements
- mod-accountbound
- mod-ah-bot
- mod-aoe-loot
- mod-eluna
- mod-guildhouse
- mod-learn-spells
- mod-reagent-bank-account
- mod-solo-lfg
- mod-solocraft
- mod-transmog

Start by tracing the mod-aoe-loot loot-handling entry point for the full-inventory path and compare it with AzerothCore's existing item-mail behavior. Reproduce the issue with a full inventory using the listed revision, then verify that looted items are mailed instead of remaining only in the loot window.

Written by the indexing model from the issue text.