feat(web): read admin lanes from the durable pass log, not a poller snapshot (#145)

The Lanes page now projects store.LatestLanePasses and the owner-window
outcomes (store.LanePassOutcomes) into per-Site rows instead of reading an
in-memory Poller snapshot, so a deploy answers the instant the store is up.
Browser configuration is a config fact and reachability is derived from
recent browser-Site passes inside latest.RefuseBackoff.

This atomically deletes the in-memory path in the same commit that makes the
page read the DB: latest/status.go (LaneState, Status, LaneStatus,
recordLaneState) and the web.LaneReporter seam plus fakeLanes are gone, and
latest.refuseBackoff is renamed latest.RefuseBackoff at every callsite.
ownerWindow (#142) is referenced, never declared (contract C2)

backend/internal/web/static/admin.css

@@ -191,6 +191,29 @@
 }
 
 /* A single grid keeps row rules continuous; cell padding supplies gutters. */
+.admin-sheet .sechead {
+  display: flex;
+  align-items: baseline;
+  justify-content: space-between;
+  gap: 20px;
+  flex-wrap: wrap;
+}
+
+.admin-sheet .sechead .statusline {
+  padding: 0 0 8px;
+  font-size: 11px;
+  letter-spacing: .14em;
+  text-transform: uppercase;
+}
+
+.admin-sheet .statusline {
+  margin: 0;
+  padding: 0 0 10px;
+  font: 500 12px/1 var(--font-mono);
+  letter-spacing: .04em;
+  color: var(--mute-2);
+}
+
 .admin-sheet .tbl {
   display: grid;
   grid-template-columns: minmax(240px, 1fr) 156px 92px 110px 76px minmax(150px, 220px) 140px;
@@ -309,6 +332,23 @@
   color: var(--mute-2);
 }
 
+.admin-sheet .mark.mark-strong {
+  font-size: 13px;
+  letter-spacing: .14em;
+  color: var(--patina);
+}
+
+.admin-sheet .mark.mark-strong::before {
+  content: "";
+  display: inline-block;
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: var(--patina);
+  margin-right: 8px;
+  vertical-align: .08em;
+}
+
 .admin-sheet .mark.bad {
   color: var(--danger);
 }
@@ -335,6 +375,10 @@
   color: var(--danger);
 }
 
+.admin-sheet .tbl.lanes .c-skip .ok {
+  color: var(--patina);
+}
+
 .admin-sheet .tbl.sites .thead > *:nth-child(n+2):nth-child(-n+5),
 .admin-sheet .tbl.sites .trow > *:nth-child(n+2):nth-child(-n+5) {
   padding-right: 0;