feat: user profile dropdown

[nimit9]

PR Fixes:

• 1 Added a profile dropdown
• 2 Made bookmark global

Resolves #307

P.S. Sorry for recording it in light mode

Added the theme toggle button after logging out, had removed it by mistake while recording this:

Screencast from 2024-04-02 17-52-15.webm

Screencast from 2024-04-02 17-50-01.webm

Checklist before requesting a review

• [x] I have performed a self-review of my code
• [ ] I assure there is no similar/duplicate pull request regarding same issue