remove 4000 character limit in accession remarks

[ccicero]

Accession Remarks is currently limited to 4000 characters. At the Arctos Workshop in February 2026, @dustymc and I talked about this and he said that was an old Oracle limit but no longer applies. Can we remove the 4000 character limit? Thanks.

[dustymc]

I don't think this needs discussion, going dev.

Current table size for baseline:

arctosprod@arctos>> select pg_size_pretty(pg_total_relation_size('trans'));
 pg_size_pretty 
----------------
 50 MB