config: missing delete command (especially with branch support)

[AndreHeller]

Problem

There is no kbagent config delete command to delete a configuration. This is especially needed when working with dev branches — deleting a config in a branch marks it as removed without affecting Main.

Workaround used

Direct Storage API call:

curl -X DELETE \
  -H "X-StorageApi-Token: <token>" \
  "https://connection.keboola.com/v2/storage/branch/{branch_id}/components/{component_id}/configs/{config_id}"

Expected behavior

kbagent config delete --project iterable --component keboola.python-transformation-v2 --config-id 1239541872

With optional --branch flag:

kbagent config delete --project iterable --branch claude --component keboola.python-transformation-v2 --config-id 1239541872

Use case

When cleaning up unused transformations in a dev branch before merging to Main, an AI agent needs to be able to delete configs programmatically without falling back to raw HTTP calls.

[padak]

Implemented in PR #42 -- kbagent config delete --project ALIAS --component-id ID --config-id ID [--branch ID] now available. Supports active dev branch by default and explicit --branch override. Thanks for the feedback!