docs: add FUTURE_WORK quality standard and close polish gaps

Replace CODE_REVIEW.md with a living maturity checklist, document
session-only History, inject Service into newMainView for testability,
add UI and scheduler regression tests, and fix RunNow error surfacing
plus empty jobs view handling.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/ui/jobs_view_helpers.go

@@ -53,5 +53,5 @@ func indexOfID(jobs []job, id int) int {
 			return index
 		}
 	}
-	return 0
+	return -1
 }