Implement Top 5 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 :)

Shipped the 5 largest LOC cuts left (−2,049 net, 77 files): prompt-library docs pages → build output (−1,476), web test harnesses (−398), frontend data hooks (−101), AST census helpers (−66), API Caller dependency (−45). Full gate green; 3 review lanes pass; PR #5405 merged (1d0f04256); Jaah Deploy success. Visual check done, no UI issues seen. Deferred: e2e fixture dedupe, terraform alarm for_each, order-dependent cron_activities test. mem-15536/15204 shaped the search.