RiboCode - add error handling where the cli tool does not

[JackCurragh]

Add lines to modules ribocode_metaplots and ribocode_ribocode to make the process fail when invalid outputs are created.

PR checklist

• This comment contains a description of changes (with reason).
• If you've fixed a bug or added code that should be tested, add tests!
• If you've added a new tool - have you followed the module conventions in the contribution docs
• If necessary, include test data in your PR.
• Remove all TODO statements.
• Emit the versions.yml file.
• Follow the naming conventions.
• Follow the parameters requirements.
• Follow the input/output options guidelines.
• Add a resource label
• Use BioConda and BioContainers if possible to fulfil software requirements.
• Ensure that the test works with either Docker / Singularity. Conda CI tests can be quite flaky:
  • For modules:
    • nf-core modules test <MODULE> --profile docker
    • nf-core modules test <MODULE> --profile singularity
    • nf-core modules test <MODULE> --profile conda
  • For subworkflows:
    • nf-core subworkflows test <SUBWORKFLOW> --profile docker
    • nf-core subworkflows test <SUBWORKFLOW> --profile singularity
    • nf-core subworkflows test <SUBWORKFLOW> --profile conda

[pinin4fjords]

Review and improvements to error handling

I've reviewed the error handling changes and made the following improvements:

Error message fixes

• Replaced pipeline-specific argument references (--extra_ribocode_metaplots_args) with module-appropriate ext.args references
• This keeps modules agnostic to how they're invoked by pipelines

Improved metaplots validation

• Issue: The original wc -l <= 2 check didn't work because the config file includes blank lines
• Fix: Now uses grep -qE '^[^#[:space:]]' to check for actual data lines (lines that don't start with # or whitespace)
• This correctly detects when no sample config line was generated

Improved ribocode error detection

• Changed grep pattern from ^Error to ^Error|Error: (with -E flag)
• This catches both line-start errors and "Error:" patterns that may appear mid-line

Added failure mode tests

• Added test test_ribocode_metaplots - empty config failure with nextflow_fail.config using -f0_percent 1.0 to force empty output
• Added test test_ribocode_ribocode - invalid config failure that creates an inline header-only config file
• Both tests verify the process fails and the error message is present in output

All tests passing locally with Docker profile.