Feature Request: Add rm <model> Command

[nikfarjam]

Description

Add a new rm <model> command to allow users to remove locally stored models when they are no longer needed.
Example:
basert rm Qwen/Qwen3-4B

Benefit

This would help users:

• Free up local storage
• Remove models installed for testing or debugging
• Replace outdated models with newer versions

Expected Behaviour

• Remove the specified model from local storage.
• Return a clear confirmation or error message.
• Handle the case where the requested model does not exist.
• Avoid accidentally removing other models or unrelated data.
• Optionally support a confirmation prompt before deletion.

Motivation

As users experiment with different models, local storage can quickly become occupied by models that are no longer required.

At the moment, there is no update command, and updating an existing model may be complex. Providing the command would make it possible to remove the existing model and then pull the latest version and cover the update use case:

basert rm <model>
basert pull <model>

[akshayatam]

This is a useful addition, especially for cleaning up locally stored models and making it easier to refresh outdated ones.

I’ve implemented the rm <model> command and added tests for the main deletion and safety cases. I’m opening a PR with the implementation.

For the update workflow mentioned here, since basert pull <model> already exists, a future explicit update path could potentially be either basert update <model> or basert pull <model> --update but I have not implemented the update behavior in this change. This PR is focused only on rm <model> as requested here.