Identify and implement five code reduction opportunities

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 :)

Five test-tree single-homings (account pinning, conftest launches/as_user, SQL write recorder over on_every_lane, seed node-group line + census/after_commit/fake-session reuse, guard factory + census path constants): 28 files, net −113. Tree measured at its clone floor (jscpd 0 web / 50 test lines); ledger of rejected leads in report. Quick gate + 1052 changed-area tests green; PR #7799 queued to the merge lane. Deferred follow-up: OpenAPI-generated types.ts. No UI surface affected.