av st sync exits with "error: reference not found"

[oleg-codaio]

Hi, somehow I managed to get my local environment in a bad state (perhaps not always using av) and now I get the following error when syncing:

➜ git:(main) av st sync --all        
                                                                                                                 
  ✓ GitHub fetch is done                                                                                         
  ✓ Restack is done                                                                                              
                                                                                                                 
    * branch1                                        
    │                                                                                                            
    │ * branch2
    │ │                                                                                                          
    │ │ * etc...
                                                                                                                 
  ✓ GitHub fetch is done                                                                                         
  ✓ Restack is done                                                                                              
                                                                                                                 
    * branch1
    │                                                                                                            
    │ * branch2
    │ │                                                                                                          
    │ │ * etc...
    ├─┴─┴─┴─┴─┴─┴─┴─┘                                                                                            
    * main d9d1c26                                                                                               
                                                                                                                 
  ⣻ Finding the changed branches...                                                                              
                                                                                                                 
error: reference not found
exit status 1

Debugging this was difficult because the Bubble Tea framework seems to clear helpful messages (I had to put opts := []tea.ProgramOption{tea.WithoutRenderer()} into tea.go), but it turns out the error is here:

av/internal/gh/ghui/push.go

Lines 436 to 439 in 8758782

	localRef, err := repo.Reference(br, true)
	if err != nil {
	return err
	}

At a later step, I got another error here:

av/internal/git/gitui/prune.go

Lines 323 to 326 in 8758782

	ref, err := vm.repo.GoGitRepo().Reference(plumbing.ReferenceName(br), true)
	if err != nil {
	return err
	}

Unfortunately I don't have a clear repro, but still wanted to file this. Is it possible to recover more gracefully from this error and still handle the other branches? Locally I could address this by appending the error to noPushBranches / noDeleteBranches or just by orphaning those branches but perhaps the UX should prompt to orphan the branch if this happens instead of crashing?