fix(tui): show error message to user if not everything was committed

[davidpdrsn]

If for some reason some hunks were rejected by but_api::commit::create::commit_create we now tell the user. Previously they just silently wouldn't be committed.

I have mostly been experiencing this because I tried to commit something to one stack would have resulted in conflicts in another. That causes a rejection. The bare minimum is to tell the user that something went wrong, which is what this PR does. It still isn't a great UX but we don't really have the APIs to improve it yet.

My opinion is that we should tell the user that there will be conflicts, before committing, but still allow making the commit. We should then also provide good tools to fix the conflicts, either before making the commit or after. That requires things like dry-runs which we are working towards.

There are also other ways to commit such as rubbing. I'll deal with those separately.

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1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
gitbutler-web	Ignored		Mar 24, 2026 2:09pm

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Pull request overview

This PR improves the legacy status TUI commit flow by surfacing partial-commit failures to the user when but_api::commit::create::commit_create rejects one or more diff specs, instead of silently dropping them.

Changes:

• Map RejectionReason values to human-readable explanations and build a multi-line error message listing rejected paths.
• Emit a Message::ShowToast error toast after commit creation when rejected_specs is non-empty.
• Simplify the Message::ShowToast enum variant formatting (and remove the prior dead-code suppression).