Manifest metadata labels generation using AllinsonFlex is not context-aware

[aploshay]

Story

The logical flow for building manifest metadata using AllinsonFlex currently does not allow for a context-aware reading of the dynamic schema, which leads to the default labels always being used when context-specific ones may be available and applicable:

• .manifest_metadata_from does not allow for a fields: argument, and calls:
  • .manifest_metadata_for, which does allow for fields: and defaults (in the context of AllinsonFlex) to calling
    • .fields_for_allinson_flex, which does allow for fields: and defaults to using:
      • .allinson_flex_fields, which directly queries AllinsonFlex::ProfileProperty entries and always uses the default labels

There's a missed opportunity here to use a dynamic schema lookup to get context-aware label values, either by allowing to pass in fields: at the start of the stack, or having .allinson_flex_fields optionally receive a work identifier to allow looking up the dynamic schema applicable to the work instead of directly querying AllinsonFlex::ProfileProperty records.

See this PR for a workaround applied to an impacted project:
IU-Libraries-Joint-Development/essi#636

Acceptance Criteria

• Metadata labels in the manifest should be consistent with context-aware flexible metadata labels on the same work's Show page