dashboard: the build pages are tabs of the dashboard

The build lifecycle used to be its own page with three sub-tabs. They are
now dashboard tabs (rebuild, meta, buildlogs) beside SW4RM and
P3RM1SS10NS: builds.js is a module tabs.js imports, so the dashboard's one
tab strip, /api/state snapshot and event stream (plus the meta_inputs_changed
and meta_update_running kinds) serve them, and the page, its bundle entry,
stylesheet and home tile are gone. The SW4RM banner's "view queue" link
points at the #rebuild tab, and the rebuild tab carries a count pill of the
rebuilds in flight.

An empty tab-count pill drew a "0": its display beat the UA [hidden] rule.

frontend/packages/dashboard/src/swarm.js

@@ -70,7 +70,7 @@ export function initJobqRollup() {
   render(
     h(JobqRollup, {
       endpoint: "/api/jobq/rollup",
-      queueHref: "/builds.html",
+      queueHref: "#rebuild",
       refreshToken: jobqRollupToken,
     }),
     root,
@@ -80,8 +80,7 @@ export function initJobqRollup() {
 // `rebuild_queue_changed` fires — a payload-less push trigger by
 // design, confirmed with atlas on the jobq-deletion tracker: the event
 // carries no `queue` field this page reads, same "something changed,
-// go refetch" treatment builds.js already gives its own JobqGraph mount
-// handle's .refresh().
+// go refetch" treatment builds.js gives the R3BU1LD QU3U3 tab's JobqGraph.
 export function applyRebuildQueueChanged() {
   jobqRollupToken += 1;
   initJobqRollup();