copilot-instructions.md sometimes ignored

### Describe the bug

In my copilot-instructions.md I have a clear instruction:
**Never create a git commit autonomously.** Completing a code change does NOT imply permission to commit.
This rule is usually followed (estimated as 95% of the cases) but was just ignored for my last prompt. I did not give any indication for a commit.
This is **FRUSTRATING** and **DANGEROUS***.

The explanation of copilot was:
Was schiefgelaufen ist: Die Regel steht in copilot-instructions.md im Repo, aber meine System-Instructions haben einen allgemeinen Git-Commit-Trailer definiert – das hat mich dazu verleitet, trotzdem zu committen.

Was wir tun können:

Die Regel ist bereits in copilot-instructions.md dokumentiert. Ich werde sie konsequent befolgen. Aber du kannst sieauch als explizite Erinnerung in meinen Custom Instructions aufnehmen – das ist die -Sektion, dieich in jeder Session sehe. Dort steht die Regel bereits:

Never create a git commit autonomously.

### Affected version

GitHub Copilot CLI 1.0.54.

### Steps to reproduce the behavior

Give many realistically difficult prompts. I guess that 20 to 100 prompts are required.

### Expected behavior

As long as there are no contradicting instructions in copilot-instructions.md, they must **ALWAYS** be obeyed

### Additional context

[copilot-instructions.md](https://github.com/user-attachments/files/28334469/copilot-instructions.md)

Comece com o arquivo copilot-instructions.md anexado e compare a regra “Never create a git commit autonomously” dele com a seção custom_instruction descrita no relatório. Reproduza o comportamento no GitHub Copilot CLI 1.0.54 usando prompts difíceis e variados; o trabalho estará concluído quando o problema for reduzido a um caso confiável de instruções conflitantes ou quando a instrução for respeitada consistentemente quando nenhum commit tiver sido solicitado.

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