feat(trips): owner publish/unpublish toggle on /trips listing

Add an owner-only publish switch to each /trips card. It POSTs to a new
entry-actions route that mutates trip.md `published` and invalidates the
page-tree cache so the listing, nav and home reflect the change on the
next load. Owner sees drafts (Draft badge); anon/non-owner unchanged.

- U1 EntryScopeGuard::resolveTripChild — resolve a slug to a direct child
  of /trips (drafts included, for republish)
- U2 POST /api/v1/trip/{slug}/publish (setTripPublished) — owner-gated
  write, strict is_bool body, header-mutation save, audit log
- U3 trip-publish-toggle partial + CSS (role=switch, Draft badge, visible
  failure toast, ≥44px target)
- U4 owner-aware /trips listing + card restructure (toggle overlays cover
  as a non-anchor sibling; works for coverless drafts)
- U5 home active-trip branch falls back when the active trip is unpublished
- U6 trip-publish.js (confirm/pending/optimistic/revert) + esbuild wiring

Cache note: an in-place frontmatter edit keeps the folder-check cache id,
and driver:auto uses APCu in web memory, so deleteAll()+invalidateCache()
is insufficient — the endpoint also calls apcu_clear_cache().

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Mpdu3Dt1iVoozHwAMyjrbn

themes/intotheeast/css/style.css

@@ -1289,6 +1289,143 @@ body::after {
 .trip-card-dates { font-size: var(--text-sm); color: var(--color-ink-2); }
 .trip-card-counts { font-size: var(--text-sm); color: var(--color-ink-muted); }
 
+/* ── Owner publish/unpublish toggle (U3) ─────────────────────────────────────── */
+/* The card is wrapped in a position:relative container so this overlay can sit
+   top-right over the cover as a sibling of the navigating <a> (KTD6). The wrapper
+   also guarantees an anchor even for a coverless draft (a min-height header strip
+   on the card itself), so the toggle never collapses to nothing. */
+.trip-card-wrap {
+    position: relative;
+}
+
+.trip-publish-overlay {
+    position: absolute;
+    top: var(--space-3);
+    right: var(--space-3);
+    z-index: 2;                         /* above the card <a> */
+    display: flex;
+    align-items: center;
+    gap: var(--space-2);
+}
+
+/* Solid pill so both indicators stay legible over an arbitrary cover photo. */
+.trip-draft-badge {
+    font-family: var(--font-ui);
+    font-size: 0.6875rem;
+    font-weight: 700;
+    letter-spacing: 0.09em;
+    text-transform: uppercase;
+    color: #E0A458;                     /* warm amber — matches .journal-draft-badge */
+    background: var(--color-canvas);
+    border: 1px solid #E0A458;
+    border-radius: var(--radius-sm);
+    padding: 0.15em 0.5em;
+    line-height: 1.5;
+    white-space: nowrap;
+    box-shadow: var(--shadow-sm);
+}
+.trip-draft-badge[hidden] { display: none; }
+
+/* The switch: a solid chip backing keeps the track/knob readable on any cover.
+   ≥44px touch target via padding; the visible track is smaller and centred. */
+.trip-publish-toggle {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    min-width: 44px;
+    min-height: 44px;
+    padding: 0 var(--space-2);
+    margin: 0;
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-full);
+    background: var(--color-canvas);
+    box-shadow: var(--shadow-sm);
+    cursor: pointer;
+    -webkit-appearance: none;
+    appearance: none;
+}
+
+.trip-publish-track {
+    position: relative;
+    display: block;
+    width: 40px;
+    height: 22px;
+    border-radius: var(--radius-full);
+    background: var(--color-ink-muted);  /* off = muted */
+    transition: background 0.15s ease;
+}
+.trip-publish-knob {
+    position: absolute;
+    top: 2px;
+    left: 2px;
+    width: 18px;
+    height: 18px;
+    border-radius: 50%;
+    background: var(--color-ink);
+    transition: transform 0.15s ease;
+}
+
+/* on = teal track, knob slid right */
+.trip-publish-toggle[aria-checked="true"] .trip-publish-track {
+    background: var(--color-accent);
+}
+.trip-publish-toggle[aria-checked="true"] .trip-publish-knob {
+    transform: translateX(18px);
+    background: var(--color-accent-on);
+}
+
+/* Pending (R13): dimmed + wait cursor while a toggle is in flight. */
+.trip-publish-toggle[aria-busy="true"] {
+    opacity: 0.55;
+    cursor: wait;
+}
+
+/* Keyboard focus ring that reads over a busy cover photo (white ring + dark halo). */
+.trip-publish-toggle:focus-visible {
+    outline: 2px solid var(--color-accent-on);
+    outline-offset: 2px;
+    box-shadow: 0 0 0 4px rgba(0, 0, 0, 0.45);
+}
+
+/* Visible page-level failure toast (R15). Distinct from feed-actions.js's
+   sr-only #feed-actions-live region: the trip card has no inline message slot,
+   so a sighted owner needs a real, visible notice. trip-publish.js creates and
+   populates the element; this only styles it. */
+.trip-publish-toast {
+    position: fixed;
+    top: var(--space-4);
+    left: 50%;
+    transform: translateX(-50%);
+    z-index: 1000;
+    display: flex;
+    align-items: center;
+    gap: var(--space-3);
+    max-width: calc(100vw - var(--space-8));
+    padding: var(--space-3) var(--space-4);
+    font-family: var(--font-ui);
+    font-size: var(--text-sm);
+    color: var(--color-ink);
+    background: var(--color-canvas);
+    border: 1px solid var(--color-error);
+    border-radius: var(--radius-md);
+    box-shadow: var(--shadow-lg);
+}
+.trip-publish-toast[hidden] { display: none; }
+.trip-publish-toast__close {
+    flex-shrink: 0;
+    min-width: 32px;
+    min-height: 32px;
+    padding: 0;
+    font-size: var(--text-md);
+    line-height: 1;
+    color: var(--color-ink-muted);
+    background: transparent;
+    border: none;
+    border-radius: var(--radius-sm);
+    cursor: pointer;
+}
+.trip-publish-toast__close:hover { color: var(--color-ink); }
+
 /* ── Trip page sidebar ───────────────────────────────────────────────────────── */
 
 .trip-counts {