validate_data() accepted category values that are not {count?, index?}
objects. They slipped through to format_entry(), which then raised
AttributeError on a normal table lookup (or serialized a malformed shape
under --json). It also accepted duplicate company names silently.
- collect_validation_issues() now also flags a non-object category value
(and non-numeric count / non number-or-string index) as a hard error,
and duplicate company names as a warning.
- validate_data() keeps its eager-fail behavior (same messages), so
existing tests and load_data() are unchanged.
- --validate runs the checks standalone and prints an actionable report
(exit 1 on errors, 0 on warnings-only/clean), letting users pre-flight
their BYO salary_data.json.
Reproduced on master: validate_data({'companies':[{'company':'Acme',
'categories':{'eng':'not_a_dict'}}]}) returns without error, but
format_entry then raises AttributeError.
Co-authored-by: Tunic Assistant <assistant@tunic.local>
