refactor(esx_multicharacter): complete UI/Backend overhaul

[l2rhydra]

Description

This PR integrates a redesigned UI for the esx_multicharacter system. It replaces the existing context menu implementation with a custom built-in UI, streamlining the user interaction experience.

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Motivation

Rebuilding the UI with modern tools and removing reliance on external context menu, this update improves the overall user experience, maintainability, and visual appeal.

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Implementation Details

• Full UI overhaul using React (with TypeScript) and Tailwind CSS v3.
• Ensured compatibility with existing ESX backend logic.
• Enhanced visual layout and user interaction flow for the multicharacter system.

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Usage Example

• Players are presented with a modern, responsive UI.
• The menu is styled to match the rest of the UI and offers smoother interactions.

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TODO

• Locales

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PR Checklist

• My commit messages and PR title follow the Conventional Commits standard.
• My changes have been tested locally and function as expected.
• My PR does not introduce any breaking changes.
• I have provided a clear explanation of what my PR does, including the reasoning behind the changes and any relevant context.

[Mycroft-Studios]

the gender doesnt seem to be showing correctly,
and background colour seems to be a tiny bit too light, i could be wrong on that one though

[l2rhydra]

Let me double check it from my side and will update

[Mycroft-Studios]

Looks good to me, seems to have just been brain trickery