[giti] giti branch checkout: Create a user experience for switching to another branch

[NadiaIdris]

Prerequisites

Install and run giti

1. Move to ./tuify folder in your terminal
2. Run nu run.nu install-giti to install giti locally to ~/.cargo/bin
3. Run giti from anywhere on your system
4. To delete one or more branches in your repo run giti branch delete

Private giti design document

Create a giti branch checkout user experience

1. Select the branch to switch to

Use select_from_list() function to display single select component. It's defined in public_api.rs file.

> giti branch checkout
Up or Down:    navigate
Return:        confirm selection
Esc, Ctrl+C:   exit program

Please select a branch to switch to 
    ◉ aaronsmith/branch-1
    ◌ (current) main
    ◌ NadiaIdris/123-branch  
    ◌ NadiaIdris/test-branch  

2. Get confirmation to have switched to the selected branch

Switched to branch ✅ NadiaIdris/123-branch

3. If user tries to switch to the current branch

You are already on branch main