Admin dashboard: pages, Lane observability, poll pass log, per-Series intervention (#134) (#148)

Spec #134, all ten tickets. Closes #134.

## What ships

The admin surface becomes four bookmarkable addresses behind one nav row, and Lane observability stops dying with the process.

- **#138** `/admin` splits into Overview, Lanes, Readers, Series, each a real route with the active tab underlined.
- **#139** `poll_passes` and `poll_lanes` land as durable tables with their store surface.
- **#140** cross-Series admin read model, with the privacy boundary in the projection: the Reader id that raised a Latest Chapter never leaves the store package.
- **#141** the poller records exactly one pass row per exit, with a skip reason and outcome counts.
- **#142** Series list: eight hygiene filters, Site and Library narrowing, paging — all of it in the query string, so a filtered list is a bookmark.
- **#143** Overview: a three-state verdict line and a stats block where every non-zero figure links to the list that counts it.
- **#144** per-Series detail page, keyed by the `site:series_id` composite the rest of the system already uses.
- **#145** the Lanes page reads the database; the in-memory Lane state, `web.LaneReporter` and `latest.Status` are deleted.
- **#146** Forced Poll: *Check now* stamps `series.force_poll_at` and never commands the poller.
- **#147** pause and resume one Site's Lane, with a mandatory 1h/6h/24h expiry.

## Shape of the design

Two decisions carry the rest. **Commands go through the database, never at the poller**: both *Check now* and a Lane pause write a row the next pass reads, so they survive a restart and the whole surface stays testable with no poller running. And **pending is derived, never stored** — the request stamp being newer than the check stamp — which self-clears on the check stamp with no second write and no sweeper, because the check stamp is written before the fetch.

ADRs: `docs/adr/0012-persisted-lane-state.md`, `docs/adr/0013-commands-through-the-database.md`.

## Verification

`go test ./...` green on the merged base (`264839e`), all packages, Docker-backed. `gofmt -l` and `go vet` clean.

Every ticket was reviewed on both axes (`cr-spec` + `cr-standards`) before merge.

## Known, non-blocking

- **#143** the verdict ignores never-reported Lanes when other Lanes have reported, and the per-Site table lists Sites that have Series rather than the whole registry. The ticket prose asks for eight hygiene figures per Site; the design mock and the landed `.tbl.sites` grid both say six columns, and the mock won.
- **#146** two `SeriesPage` scans per press instead of a keyed read — `ponytail:`-commented in-tree with the upgrade path.
- **#147** a paused Site with no pass row yet renders no row and so no control, since the Lanes page lists Sites that have passed.
- **#141** a sibling browser Lane declining at the top of a pass records as `sidecar-down`. Specified deliberately; the later spec in this series settles it.

Reviewed-on: #148
Co-authored-by: Sulthan Zaki <sultankiki05@gmail.com>
Co-committed-by: Sulthan Zaki <sultankiki05@gmail.com>

backend/internal/web/static/style.css

@@ -296,69 +296,6 @@ button { cursor: pointer; }
   letter-spacing: .04em;
 }
 
-/* ---- admin page: two sections on the same measured sheet, no cards ----
-   The reading page is a list of series; this is a list of facts. Both are
-   sheets of hairline-separated rows, so the roster keeps the shape it had as
-   a fold-out and the Lane block copies it. */
-.readers, .lanes { margin: 0 20px; padding: 12px 0 16px; border-bottom: 1px solid var(--rule); }
-.readers h2, .lanes h2 {
-  margin: 0;
-  padding: 8px 0;
-  font: 500 10px/1 var(--font-mono);
-  letter-spacing: .2em;
-  text-transform: uppercase;
-  color: var(--mute-2);
-}
-.readerlist, .lanelist { margin: 0; padding: 0; list-style: none; }
-.readerlist li, .lanelist li {
-  display: flex;
-  align-items: center;
-  flex-wrap: wrap;
-  gap: 4px 16px;
-  min-height: 44px;
-  border-top: 1px solid var(--rule);
-}
-.reader-actions { display: flex; gap: 18px; margin-left: auto; }
-.readerlist form { margin: 0; }
-.reader-id {
-  font: 500 13px/1.4 var(--font-mono);
-  letter-spacing: .04em;
-  color: var(--paper);
-}
-.reader-sessions {
-  font: 500 10px/1 var(--font-mono);
-  letter-spacing: .14em;
-  text-transform: uppercase;
-  color: var(--mute);
-}
-.reader-sightings, .lane-fact {
-  font: 500 10px/1 var(--font-mono);
-  letter-spacing: .14em;
-  text-transform: uppercase;
-  color: var(--mute-2);
-}
-/* Two states the owner is meant to find rather than read for: a Reader whose
-   reports no longer defer a Poll, and a Lane that is not keeping its promise.
-   Both wear --patina — never ember, which means one thing, and never danger,
-   which is destruction. */
-.reader-blocked, .lane-mark {
-  font: 500 10px/1 var(--font-mono);
-  letter-spacing: .14em;
-  text-transform: uppercase;
-  color: var(--patina);
-}
-.lane-site {
-  font: 400 19px/1.2 var(--font-display);
-  color: var(--paper-dim);
-}
-/* The whole row leans patina when the Lane needs attention, so the scan is one
-   pass down the left edge rather than a read of every mark. */
-.lanelist li.attention .lane-site { color: var(--patina); }
-.lane-browser { padding: 12px 0 0; }
-/* Revocation cuts someone off, so it wears --danger. Ember stays reserved for
-   the new-chapter signal. */
-.ghost.danger { color: var(--danger); }
-.ghost.danger:hover { color: var(--danger); border-bottom-color: var(--danger); }
 
 .chrome { display: flex; flex-direction: column; }
 
@@ -643,9 +580,6 @@ button { cursor: pointer; }
   box-shadow: inset 0 -2px 0 var(--ember);
 }
 .topbar form { margin-left: 18px; }
-/* The admin page's topbar has no switch to fill the middle, so its back link
-   keeps company with Log out at the right edge instead of floating centre. */
-.topbar .back { margin-left: auto; }
 /* At phone width brand + switch + Log out do not fit on one line, so the
    switch takes its own row under the wordmark rather than pushing Log out
    off-screen. */
@@ -655,9 +589,6 @@ button { cursor: pointer; }
   .libswitch { order: 3; margin-left: 0; }
   .libswitch a { flex: 1; text-align: center; padding: 8px 14px; }
   .topbar form { margin-left: 12px; }
-  /* The admin page has no switch to take the second row, so its brand claims
-     the first outright and the back link keeps Log out company below. */
-  .topbar:has(.back) .brand { flex: 1 1 100%; }
 }
 
 /* ---- action strip: full-width on a phone, hairline-divided cells ---- */