Description:
Currently, the small_molecule_evidence table in mzTab-M only includes features or spectra that have an annotation. This makes it impossible to track MS/MS spectra that were acquired but did not match any known compound.

Proposed change:

1. Add entries to the small_molecule_evidence table for unannotated MS/MS spectra.
2. For these entries, populate the following fields:
   • identifier (or name) = null
   • evidence = 0
3. Introduce a new optional column to indicate MS/MS matching status:
   • opt_global_MSMSmatched → value can be TRUE or FALSE