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

Net −399 lines (59 files): web pages moved onto useSubmit, shared formatters, FormDialog and shared billing/drawer pieces; 4 dead exports and 3 Python fns deleted. PR #4826 merged, CI gate and Jaah Deploy green. Rename/identity shims deferred (fleet-gated).