Issue 14 — Add .listitems inventory listing command - MEDIUM

[Irresistible-Ishan]

Description
A command to display the bot’s full inventory contents with quantities.

Technical Notes
Use inventory items list:
bot.inventory.items()

Example output:

Inventory:
3x Oak_Log
1x Iron_Pickaxe

Acceptance Criteria

Prints item names & quantities

Handles empty inventory ("Inventory is empty")

Labels: medium, inventory, feature