--validate treats an explicit "metadata": null / "categories": null the same
as an omitted key ("...must be an object when provided", None is skipped), but
format_entry read both through dict.get(key, {}), which only substitutes the
default for an *absent* key - a present-but-null value passed through. The
renderer then hit None.get("index_label", ...) (AttributeError) or, via the
numeric-field fallback, None[key] = value (TypeError), so a hand-maintained
salary_data.json using null for "no value" died with an uncaught traceback
right after printing "Found 1 match(es)".
format_entry now coerces both to {} up front, honouring the validator's
existing "when provided" contract at the single consumer that broke it.
Tests (all verified to fail on the unfixed renderer):
- two unit cases calling format_entry with null metadata / null categories
- two end-to-end cases running main() --validate (blesses the file) then the
lookup path (renders it), one per null shape
Plus an [Unreleased] CHANGELOG entry.
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
