Feat: Configurable Discovery, Discovery libraries, and Consistent Error Codes

[ClassicMMT]

Added

• Configurable discovery support.
• Discovery configuration management: list, view, create, update, delete, validate, and status.
• Discovery configuration library management: list, view, create, update, delete, validate, and status.
• Start schema discovery or file discovery from a saved discovery configuration.
• Download the discovery configuration that a run used.
• Validation status for rulesets and ruleset libraries.
• Safe data preview in the machine-readable output of schema discovery results and file discovery reports.
• A command to start file data discovery.
• A size limit for immediate validation.
• An exit code for a declined confirmation, and an exit code for insufficient permission.
• A line number and a column number for each validation error.
• Support for the current DataMasque Python client release.

Changed

• Ruleset library validation exits with an error code when the library is invalid.
• Server and network failures give a message and an exit code, not a traceback.
• File failures name the file.
• A declined confirmation is no longer reported as a failure.
• A run start or a run retry returns only the run identifier in machine-readable output.

Fixed

• Ruleset validation reported an invalid ruleset as valid.
• Ruleset generation, connection password updates, and the deprecated import command.

[ClassicMMT]

Requires dm-python SDP PR and dm-python configurable discovery PR to be merged and dm-python==1.1.8 published on PyPI.

Note to self: once dm-python==1.1.8 is published, need to update uv.lock.

[kw-datamasque]

I like this idea of abort_api_error() which shows DataMasque's errors instead letting Typer handle errors itself.

However it may be easy to forget to add it in specific CLI commands - claude has found a few above. Preferably we would use these new abort_...() functions consistently across all the commands.

Could we create a top-level safety net, does something like the following work? (claude)

  def main() -> None:
      try:
          app()
      except DataMasqueApiError as exc:
          abort_api_error("Request failed", exc)
      except DataMasqueTransportError as exc:
          abort(str(exc), code=ErrorCode.TRANSPORT_ERROR)

Apart from consistently using abort_...() family and the UTF-8 issue above, most of the other comments are minor and this will be a good addition to the DataMasque CLI

[ClassicMMT]

@kw-datamasque Thanks for your review!

The suggestions were great and I've implemented all of them and some more.

[kw-datamasque]

I roleplayed a tester and had Claude test the modified CLI surface to see if it received reasonable outputs.

It found 6 of the 14 comments below (2 pre-existing), marked with (Claude) followed by Input, Expected, Reason, Suggestion for reproducibility.

I've placed Suggestions to most comments hopefully these are easy fixes. The other comments are mostly tidy ups.

[kw-datamasque]

Almost there- Two small asks before merge:

1. Could you please add a PR description as a best practice? Doesn't need to be super polished.

2. Could the title reflect the full scope too? Something like "feat: configurable discovery, discovery libraries, consistent error codes"