RM-106: Prevent tag from being created if over discord's character limit

[biast12]

Description

RM-106
Introduces a check to ensure total embed characters do not exceed Discord's 6000 character limit when creating tags.

Also noticed some of the max values where wrong, content got a 2000 character limit (was 4096 before) and the others got a 256 character limit (was 255 before)
https://discord.com/developers/docs/resources/message#create-message
https://discord.com/developers/docs/resources/message#embed-object-embed-footer-structure

Type of Change

• Bug fix
• New feature
• Breaking change

Testing

i tried to make a tag with a lot of fields with a lot of text

Checklist

• My code follows the style of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works