Remove message commands and rewrite code implementation and functions

[JoshuaSlui]

This pull request provides readability, documentation and rewrites of the code, functions, commands and methods we use.
To be precise, this pull request handles:

• Changing contact mail in SECURITY.md
• Removing unnecessary utils.respond & help_CMD functions
• Fixes code formatting for readability
• Applies PEP8 conventions everywhere
• Removes obsolete imports
• Adds documentation to (some) functions
• Adds functions to handle database queries
  • Modifier
  • Selector
• Adds venv to .gitignore
• Adjusts code to use new utility folder & relevant files/functions
• Fixes @Soapy7261's spelling mistakes
• Fixes markdown files, primarily tables
• Fixes blacklisted servers still being able to add Pingernos
• Allows deleting setserver servers from database by not providing a server
• Adds check_ip function using regex
• Actually require a server IP in checkip
• ⚠️ Complete migration to slash commands

When approved and merged, PR 56 will mark release 3.0.0.
After release 3.0.0, we will start releasing appropriately for all new commits.

[JoshuaSlui]

The Pull Request now fully migrates all commands to slash commands, implements additional features that simplifies, and decreases the amount of code needed. When this Pull Request is reviewed, we can work on applying the DRY (Don't Repeat Yourself) principle to all the code.

[zortos293]

few things that need to be fixed

[zortos293]

Forgot the ephemeral on the error's

my bad ;)

[zortos293]

Good to go 👍