Reduce repository code by implementing top five

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 :)

Folded 35 alembic revisions into baseline 202610311800 (net −2,185 lines), proved by schema and row-set identity; PR #7516 merged at 8cc00e5dc, Jaah Deploy green. Resume re-census (vulture, knip, 4 recon lanes) found no further fold; the other four cuts (test volume, generated types.ts, legacy CLI runtime, Windows platform) are ADR decisions, named not built. No UI surface affected. Memory: used mem-31415, mem-31667; proposed 1 qa.