Removed old references to miauw and signal

[ammar92]

Changes

Removed some dead code and references to Miauw and Signal

Proof

Searching miauw and signal using find usages option and grep yields no results anymore.

Good to know

• Does this PR introduce or depend on API-incompatible changes? If yes: what do other users/developers need to do or confirm before merging?
  • No
• Does this PR depend on a specific version of a library?
  • No
• Does this PR require config, setup, or .env changes?
  • Yes, settings related to miauw can be removed safely

Checklist for author(s):

• This PR comes from a feature or hotfix branch, in line with our git branching strategy;
• I have squashed all commits before merging this PR;
• This PR is "bite-sized" and only focuses on a single issue, problem, or feature;
• If a non-trivial PR: This PR is properly linked to an issue on the project board;
• If a non-trivial PR: I have added screenshots or some other proof that my code does what it is supposed to do;
• I am not reinventing the wheel: there is no high-quality library that already has this feature;
• I have changed the example .env files if I added, removed, or changed any config options, and I have informed others that they need to modify their .env files if required;
• 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, if necessary;
• I have written unit, integration, and end-to-end tests for the change that I made;