Minor updates to uv project export machinery in PyRosettaCluster

[klimaj]

This minor PR addresses:

• Adds the --no-annotate --no-header flags to the uv export command, instead of relying on a custom remove_comments() subfunction.
• Ensures the self.toml_format attribute is still set for the edge case where the uv pyproject.toml file cannot be automatically located via either the UV_PROJECT environment variable or the current working directory (which currently leads to an AttributeError upon saving results). A more helpful warning message is provided herein.
• Disables two FutureWarnings regarding the filter_results and norm_task_options class attributes being enabled by default, which were introduced in version 2.1.0 (merged ~8/25) and 3.0.0 (merged ~10/25), respectively.