Scientific Metadata with / without '.value' (or ' .v')

Scientific Metadata with / without '.value

Summary

when working on https://github.com/SciCatProject/scicat-backend-next/pull/119 we saw that for the new SciCat backend there is currently no support for metadata outside the '.value', '.unit' scheme. In https://github.com/SciCatProject/scicat-backend-next/issues/119#issuecomment-1201236240_ there is an example of scientific metadata from PSI that falls in this category:

Originally posted by @stephan271 in https://github.com/SciCatProject/scicat-backend-next/issues/119#issuecomment-1201236240

Expected Behaviour

like in the old backend the frontend search should work also on any string and integer values in the metadata without having a 'unit' / 'value'. Further in the example above 'v' and 'u' instead of 'value' and 'unit'.

I have the feeling it would make sense to provide a sort of generic helper to deal with the different options of having .value, .value+.unit or none of them. Currently '.value' is hardcoded in the new backend code e.g.

src/common/utils.ts:20:    return { valueSI: Number(quantity.value), unitSI: quantity.unit };
src/common/utils.ts:92:    const matchKeyMeasurement = `scientificMetadata.${lhs}.valueSI`;
src/common/utils.ts:97:        scientificFilterQuery[`${matchKeyGeneric}.value`] = { $eq: rhs };
src/common/utils.ts:102:        scientificFilterQuery[`${matchKeyGeneric}.value`] = { $eq: escapedRhs };
src/common/utils.ts:111:          scientificFilterQuery[`${matchKeyGeneric}.value`] = { $eq: rhs };
src/common/utils.ts:121:          scientificFilterQuery[`${matchKeyGeneric}.value`] = { $gt: rhs };
src/common/utils.ts:131:          scientificFilterQuery[`${matchKeyGeneric}.value`] = { $lt: rhs };
src/datasets/interceptors/fullquery.interceptor.ts:34:                `${lhs}.value`,
src/datasets/interceptors/fullquery.interceptor.ts:46:                  `${lhs}.value`,