Identify and implement top 5 code reduction

Identify top 5 opportunities 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 - A front end component or a group of them duplicate another component/page functionality. Use the most modern and nice looking - etc. Now implement them :)

No PR: nine dead-code and clone scans over source and tests find no reduction above ~25 lines; the tree is at its floor (mem-35769 confirmed). The five remaining candidates are owner decisions (Windows backend, legacy launch per ADR-0167, edition maps, GitHub Connect, production_qa fold), sized in the report. Decided not to delete shipped surfaces unasked. No UI surface affected.