Added /note command

[Zabuzard]

Overview

Implements and closes #349. This adds the /note command, which allows moderators and Staff Assistants to write a note about a given user, which is then accessible via /audit.

It is basically like /warn, but without noticing the target user.

Here is an example of how the /audit looks like:

Details

There are the usual edge cases that are handled similar to other moderation commands:

• target user is too powerful for bot to interact with
• target user is too powerful for command user to interact with
• comamnd user is lacking the required role (soft moderation)

[sonarqubecloud]

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0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[Zabuzard]

Merged since Heatman previously approved and nothing really changed since then.