Implement per-message profile management and sending with a per-message profile

[dozro]

Description

Fixes #298
Implements usage of MSC4144

for future development: #340 and #341

This pull request introduces support for per-message profiles (PMP), allowing users to set and use different profiles (such as display name, avatar, and pronouns) on a per-message basis. It adds both backend logic and UI components for managing these profiles, updates the message sending and rendering logic to support PMP, and exposes new settings and commands for users to interact with this feature. Additionally, it refactors some settings components for better modularity.

The most important changes are:

Per-Message Profile (PMP) Support:

• Added logic to send messages with a per-message profile if one is selected, including updating the message content to include the PMP data (com.beeper.per_message_profile).
• Added new commands (/usepmp, /addpmp, /delpmp) to manage and use per-message profiles via the chat input.

Settings UI Enhancements:

• Introduced a new "Persona" section in the settings, with a dedicated page (PerMessageProfilePage) and overview/editor components for managing per-message profiles. (open to suggestion where that belongs lol)

Pronoun Handling Refactor:

• Moved PronounSet and parsePronounsInput to a shared utility file for consistent usage across the codebase, and improved pronoun filtering logic in the timeline.

Settings Refactoring:

• Refactored the animal cosmetics ("cat" settings) into a standalone component for better modularity and maintainability.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines 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

[dozro]

i missed theby msc suggested fallback

(thanks @tulir for pointing it out, that it is optional /gen)

[tulir]

i missed the mandatory fallback, as required by spec

Adding the fallback isn't mandatory, that's why there's the has_fallback flag to tell if a fallback is present or not. Having it is probably good for this use case though

[dozro]

Adding the fallback isn't mandatory, that's why there's the has_fallback flag to tell if a fallback is present or not. Having it is probably good for this use case though

well having a fallback makes sense, so i added it 🤷‍♀️ , sorry for misunderstanding the msc

and thanks for pointing it out :3 (/gen)