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 the five remaining duplicated mechanisms (jaahd AF_UNIX dial seam, API + jaahd sibling-function folds, one e2e feed-geometry oracle, shared NodeLink poll/chip): −141 lines, behaviour unchanged. Quick gate, 613 API + 740 jaahd + 1689 web tests, both review lanes green. PR #7541 queued in the merge lane. Recon showed the tree already swept (~16 prior dedup tasks); the only large candidate (legacy runtime) is a product decision, and the preferences shim stayed because cp_psql was refused.