initial plugin metadata extraction

[JFRudzinski]

Summary

This PR adds the first metadata extraction for nomad-simulation-parsers using the nomad-plugin-metadata pipeline.

What to review

Please review nomad_plugin_metadata.yaml.
This is the canonical, merged file intended for querying/registry usage.

How files work

• .metadata/nomad_plugin_metadata.auto.yaml
  Machine-generated metadata from package/plugin introspection.
• .metadata/nomad_plugin_metadata.manual.yaml
  Maintainer-owned manual curation/overrides (not machine-overwritten).
• nomad_plugin_metadata.yaml
  Final merged output (auto + manual; manual non-empty values take precedence).
• .metadata/plugin-metadata.override-report.yaml
  Report of conflicts where manual overrides auto.

Goal of this PR

Initial extraction pass for developer feedback before broader rollout:

• verify extracted parser/file-format metadata
• identify missing/incorrect fields
• align expected manual curation scope

References

• nomad-plugins-metadata: https://github.com/FAIRmat-NFDI/nomad-plugins-metadata, https://fairmat-nfdi.github.io/nomad-plugins-metadata/reference/schema_reference.html#full-schema-shaped-yaml-template
• datatractor: https://github.com/datatractor