feat: GitHub Link Preview Details (Optimised & light)

[ARYPROGRAMMER]

This Adds the Feature Mentioned in Issue#328
This PR also Solves the Issue of App Being Slow as mentioned in the Previous PR Here

Specifically, for all stories with a GitHub Repo preview I have added an Enhancement to the existing UI to fetch the details of the repo specified and give its preview without even opening it. Thereby providing the user a more seamless experience.

• Added Bloc State Management for Github Repo Fetching to Reduce Core time lag and latency with seamless UX
• Since no FutureBuilder is used only one API call is given reducing the widget tree overflow errors
• All features are Working
• Free and Flexible to Change further, Main Logic Implemented Separately
• No Breaking Changes
• Added Enhancement requires Admin's GitHub PAT (Personal Access Token)
• No Render Issues or Time Lags Observed

Sample Image :

Sample Video :

[ARYPROGRAMMER]

@Livinglist I request you to kindly perform the minor changes before releasing, and also that the feature is decoupled from repo , you can merge this and then flexibly change it around as your convention and needs as I tend to fall short and will most probably break some underlying architecture. Moreover the function needs only a little refinement which only you could do.

[ARYPROGRAMMER]

@Livinglist can you run ci for this and get this going

[ARYPROGRAMMER]

@Livinglist any updates on this?