CLI: Use getattr on conditional args, Check handler type. Debug log in get_attr

[jambayk]

Describe your changes

CLI:

• For command arguments like task, adapter_path, and trust_remote_code, use getattr to avoid AttributeError in case the handler type is not supported.
• Add assertions in the commands to ensure the expected model handler type is provided

utils:

• get_attr logs a debug message instead of a warning message. This util is used to find optional submodules so we should not log as warning.

workflow.run:

• default passes to an empty dict. Otherwise, some other code tries to use dict methods on None.
   

Checklist before requesting a review

• Add unit tests for this change.
• Make sure all tests can pass.
• Update documents if necessary.
• Lint and apply fixes to your code by running lintrunner -a
• Is this a user-facing change? If yes, give a description of this change to be included in the release notes.
• Is this PR including examples changes? If yes, please remember to update example documentation in a follow-up PR.

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