P2R-02 follow-up: clickable rows on Sources/Schedules + cron-preset tooltips

Aligns Sources and Schedules tab rows with the dashboard's row-click
UX: whole-row click navigates to the row's edit page (mirroring
.host-row.clickable). Drops the redundant Edit buttons; Run-now and
Delete remain in .row-action cells that sit above the row-link
overlay via z-index.

Schedule edit form's cron preset chips now carry human-readable
title= tooltips ("Every day at 03:00", "Every Sunday at 03:00", etc).

tasks.md gets a binding row-design rule covering all current and
future list-row templates, and the P2R-02 entry is split into the
six slices already agreed with the operator (slices 1–3 marked
done, 4 next).

CLAUDE.md

@@ -2,6 +2,14 @@
 
 Project-specific rules for Claude when working in this repo.
 
+## Run `go vet` before every commit
+
+CI runs `go vet ./...` and will fail the build on any vet error.
+Run it locally before staging a commit and fix anything it flags.
+A common one is `res, _ := http.Do(...); defer res.Body.Close()` —
+if `err != nil` then `res` may be nil and the deferred close
+panics. Always check the error before touching `res`.
+
 ## No `Co-Authored-By` trailers on commits
 
 Don't add `Co-Authored-By: Claude ...` (or any other co-author