Enable `just fetch-reference` to take a list of IDs

[caufieldjh]

This would be a very minor convenience feature, but one that the agents seem to think should exist already: allow just fetch-reference to take a list of IDs as input.
Otherwise, they encounter an error:

$ just fetch-reference PMID:22151899 PMID:30232040
error: Justfile does not contain recipe `PMID:30232040`
error: Justfile does not contain recipe `PMID:30232040`

[github-actions]

Issue Summary

This is a developer experience enhancement for the fetch-reference justfile recipe. Currently, the recipe only accepts a single PMID/reference ID at a time, which is inconvenient when AI agents or users need to fetch multiple references in one command.

Current Implementation

The fetch-reference recipe at line 546 of project.justfile:

fetch-reference pmid:
    uv run linkml-reference-validator cache reference {{pmid}}

Problem

When attempting to pass multiple PMIDs:

$ just fetch-reference PMID:22151899 PMID:30232040
error: Justfile does not contain recipe `PMID:30232040`

Just interprets the second PMID as a separate recipe name rather than an additional argument.

Solution

The recipe should be updated to accept variadic arguments using just's *args or +args syntax:

Option 1: Zero or more arguments (using *args)

fetch-reference *pmids:
    #!/usr/bin/env bash
    for pmid in {{pmids}}; do
        echo "Fetching reference: $pmid"
        uv run linkml-reference-validator cache reference "$pmid"
    done

Option 2: One or more arguments (using +args)

fetch-reference +pmids:
    #!/usr/bin/env bash
    for pmid in {{pmids}}; do
        echo "Fetching reference: $pmid"
        uv run linkml-reference-validator cache reference "$pmid"
    done

Option 2 is recommended as it requires at least one PMID (preventing empty calls).

Expected Behavior After Fix

# Single reference (existing behavior maintained)
just fetch-reference PMID:22151899

# Multiple references (new capability)
just fetch-reference PMID:22151899 PMID:30232040 PMID:12345678

# Batch fetching for curation work
just fetch-reference PMID:22151899 PMID:30232040 NCT05813288

Impact

• Low complexity: 5-line change to project.justfile:546
• High value: Reduces friction for AI agents and human curators working with multiple references
• No breaking changes: Single-argument usage remains identical

Related Context

This pattern is commonly needed during evidence validation workflows where multiple papers need to be cached before running:

• just validate-references kb/disorders/MyDisease.yaml
• just qc
• just validate-all

The reference cache (references_cache/) stores fetched PubMed abstracts and ClinicalTrials.gov data to avoid repeated API calls during validation.

Labels Recommendation

• enhancement: Feature improvement
• developer-experience: Improves tooling workflow
• good-first-issue: Simple, well-scoped change