Allow deleting local branch even if no remote exists

[codeNilson]

Is your feature request related to a problem? Please describe.
Currently, when using the "Delete local and remote branch" option, if the branch has no remote counterpart, LazyGit shows a warning and refuses to proceed. This can be inconvenient when working with local branches only — especially in workflows where branches are temporary or not always pushed to remote.

Describe the solution you'd like
If the selected branch has no remote, LazyGit should still allow deleting the local branch without showing a warning or error. Ideally, it would just skip the remote part and continue with deleting the local branch silently.

Describe alternatives you've considered
Manually switching to "delete local branch" instead, but this adds friction and defeats the purpose of the "delete both" shortcut.

Additional context
This would help make the UX more fluid for users who often work with local branches only or in detached workflows.
Similar feature for branches was recently implemented #4203

[stefanhaller]

I don't understand. Deleting a local branch is as simple as pressing d enter. Why do you want to press d b instead, and expect that to work?

[codeNilson]

I don't understand. Deleting a local branch is as simple as pressing d enter. Why do you want to press d b instead, and expect that to work?

True, but the point of d + b is convenience — feels unnecessary to block it over a missing remote. Would be a simple, non-disruptive quality-of-life improvement.