Add rotation-based offsets

[jie65535]

Description

Allows the player to teleport or spawn based on the character's current rotation direction.

A new position identifier ^ is added to represent the position offset based on the current player orientation.

Example:
Move forward: /tp ^ ^ ^10
Move backward: /tp ^ ^ ^-10
Move right: /tp ^10 ^ ^
Move left: /tp ^-10 ^ ^
Spawn in front of player: /spawn id ^ ^ ^10

Type of changes

• Bug fix
• New feature
• Enhancement
• Documentation

Checklist:

• My code follows the style guidelines of this project
• My pull request is unique and no other pull requests have been opened for these changes
• I have read the Contributing note and Code of conduct
• I am responsible for any copyright issues with my code if it occurs in the future.