fix(cropper): make load failures visible; loud config errors

'Load next queued' did nothing because the running server had been started
without its env file (a restart used '-f .env' from tools/, where no .env
exists), so the cropper was unconfigured and every action answered 503 —
and none of that was visible, because notifications never rendered either:

- notifications used cds-toast/cds-toast-item, which the Carbon bundle does
  not define; a cds-toast-notification element renders nothing standalone in
  this build. The cropper now uses cds-inline-notification in the fixed
  toast viewport (renders, themed, close button) like the wizard
- an unconfigured deployment now says so on the page (503 'Cropper
  unavailable') instead of rendering actions that all fail, and logs a
  startup warning naming the missing credentials
- tests: notifications use a registered element; unconfigured page 503

tools/public/assets/style.css

@@ -20,7 +20,7 @@ body.app {
 /* prevent FOUC on web components */
 cds-button:not(:defined), cds-tag:not(:defined), cds-tile:not(:defined),
 cds-clickable-tile:not(:defined), cds-inline-notification:not(:defined),
-cds-toast:not(:defined), cds-toast-item:not(:defined), cds-progress-bar:not(:defined) {
+cds-progress-bar:not(:defined) {
   visibility: hidden;
 }
 /* Carbon styles the shadow anchor inside tiles, not the host — give the host
@@ -183,7 +183,8 @@ cds-button::part(button) { font-size: 14px; }
 .review-options .form-check { margin-bottom: 0.35rem; }
 
 /* ── notifications viewport (cropper toasts) ────────────────────────────── */
-.toast-viewport { position: fixed; top: 3.5rem; right: 1rem; z-index: 1100; width: min(360px, calc(100vw - 2rem)); }
+.toast-viewport { position: fixed; top: 3.5rem; right: 1rem; z-index: 1100; width: min(380px, calc(100vw - 2rem)); display: flex; flex-direction: column; gap: 0.5rem; }
+.toast-viewport cds-inline-notification:not(:defined) { visibility: hidden; }
 
 /* ── footer ─────────────────────────────────────────────────────────────── */
 footer.foot { flex-shrink: 0; padding: 1.1rem 0 1.3rem; color: var(--cds-text-helper, #6f6f6f); font-size: 12px; border-top: 1px solid var(--cds-border-subtle, #c6c6c6); }