Support directory input for `completeness` command

[wiebe-vandendriessche]

Problem or motivation

• completeness only accepts a single file via --input

• Cannot compute scores for multiple AIBOMs in a directory

• aibomgen typically outputs multiple BOMs per run

• Users must manually script iteration

• Current flow:

  bom, err := bomio.ReadBOM(inputPath, inputFormat)

  assumes a single file and couples parsing with execution

• No batch processing support:

  • no file discovery
  • no filtering by .json / .xml
  • no aggregation of results

• Limited usefulness in automation:

  • cannot compute scores across a dataset
  • no average or summary metrics
  • --plain-summary only works per file

Proposed solution

• Extend --input to accept:

  • single file
  • directory

• Add directory handling:

  • detect directory input
  • list and filter .json / .xml files
  • optional recursive traversal

• Batch processing:

  • run completeness check per file
  • collect results across all BOMs

• Improve output:

  • per-file scores
  • aggregated summary:
    • average score
    • total files
    • distribution (optional)

• Extend --plain-summary:

  • support multi-file output (one line per file)
  • optional aggregated summary line

• Refactor:

  func ListBOMFiles(path string) ([]string, error)

Alternatives considered

• Keep single-file model and rely on external scripting

  • rejected due to poor UX

• Add separate batch command (e.g. completeness-dir)

  • rejected due to duplication

• Only support glob input

  • less intuitive than directory support

Additional context

• Needed for evaluating multiple generated AIBOMs
• Improves integration with CI pipelines and benchmarking workflows
• Consistent with expected behavior of analysis tools