Implement Massive Repository Code Reduction

Identify an opportunity to massively reduce the amount of code (lines of code) in any part of the repo: - Similar functionality that can be unified and reused - Code that has been valuable but no more - Front end component or group of them duplicates another component functionality. Use the most modern and nice looking - Move to DBOS and get rid of supporting functionality relying on DBOS - etc. Implement it

PR #5151 merged and deployed: shared jaahd marker-write helper, folded duplicate price/date formatters, net −22 lines, CI green. No safe "massive" cut exists; the large ones (rename compat, identity contraction) are deferred in the report.