Fixing Usability: Retain project selection when navigating to settings,search etc

[dibyanshu-pal-kushwaha]

Description: This PR addresses by preserving the currently selected project when navigating away from the current selected project to Settings, Search, or About etc and returning.

Fixes : #287

Changes :

1. Created contexts/Projects.js : Created a new React Context to manage shared project state.
2. Updated App.js : Moved selectedProjectId to App, making it the single source of truth and Context Provider.
3. Updated app/routes.js : Updated app/Routes.js to wrap ProjectPage with the context consumer and pass global state and setter as props.
4. Modified Project.page (ie : handleSelectProjectListItem & handleLoadProjectListResponse)

Screenshots:
Selected a project :
Opened and selected any project:

Clicked on the Search option :

Finally comeback to HomePage and the selected Project remained as it was: