Add allow/disallow list to bash tool

[srtab]

Now the bash tool as no restrictions on commands that it can run. The only restriction in place is on bash tool description (prompt) which easily is bypassed/not respected by some models.
Adding an disallow list for certain commands, for instance, git commit and push, will be more safe.
But there's some challenges in doing this, as the llm can run multiple commands on one run.
It will be interesting to allow users configure these as a setting too.

[srtab]

A tool like https://github.com/ldayton/Parable could help a lot on this task.