fix(ui): a write that fails says what failed and why, wherever it fails

`req` opens its blocking dialog for 400/409/422/5xx only. A 403/404/429 was left to the caller and a
502-504 or lost connection got just the self-clearing connection notice, so 34 mutations without a
reporting onError and 15 direct api writes with a bare or missing catch failed in silence: a hidden
channel that snapped back, a share link that never revoked, a confirmed account delete that ended
with nothing said.

- lib/queryClient: one MutationCache reporter. react-query awaits it BEFORE the mutation's own
  onError, so it waits a task and skips a failure the site already reported; the toast title comes
  from `meta.failTitle`, `meta.errorShownInline` opts out.
- notifyActionError: title names WHAT failed, the line under it says WHY (`failureReason`: a
  structured localized detail, else the status). It marks the error reported (`markReported`), so
  nothing reports one failure twice; `notifyKnownFailure` for a site's own specific sentence.
- Every silent site named (45 new HU/EN titles, 4 reasons). Stale "the global dialog shows it"
  comments corrected on the job actions, channel block, Plex sync, cookies, download enqueue,
  account delete and usePref.
- Channels passed the tag hook's channel id to the reporter as the error; the tag and priority hooks
  now report themselves, with the real error.
- A contract test keeps every useMutation naming its failure; CLAUDE.md gains the pattern row.
- history.dom.test: the "navigates only once the entries are back" assertion raced an async act's
  macrotask flush (1 in 5 runs); it now asserts from a later popstate listener.

frontend/src/components/AccountPanel.tsx

@@ -7,6 +7,7 @@ import { LoadingState, StateMessage } from "./ui/QueryState";
 import { api } from "../lib/api";
 import { qk } from "../lib/queryKeys";
 import { notify } from "../lib/notifications";
+import { notifyActionError, notifyKnownFailure } from "../lib/actionErrors";
 import { copyText } from "../lib/clipboard";
 import { invalidateUserAccess, isEmailOff } from "../lib/adminUsers";
 import type { AdminUserAccess, AdminUserRow } from "../lib/api/admin";
@@ -66,25 +67,22 @@ export default function AccountPanel({
   const issue = useMutation({
     mutationFn: () => api.createSetPasswordLink(user.id),
     onSuccess: (r) => setLink({ url: r.url, expires_at: r.expires_at }),
-    onError: () => notify({ level: "error", message: t("users.account.linkFailed") }),
+    onError: (err) => notifyActionError(err, t("users.account.linkFailed")),
   });
 
   const resend = useMutation({
     mutationFn: () => api.resendUserVerification(user.id),
     onSuccess: () => notify({ level: "success", message: t("users.account.resendSent") }),
     onError: (err) =>
-      notify({
-        level: "error",
-        message: isEmailOff(err)
-          ? t("users.pendingAccess.resendEmailOff")
-          : t("users.pendingAccess.resendFailed"),
-      }),
+      isEmailOff(err)
+        ? notifyKnownFailure(err, t("users.pendingAccess.resendEmailOff"))
+        : notifyActionError(err, t("users.pendingAccess.resendFailed")),
   });
 
   const activate = useMutation({
     mutationFn: () => api.activateUser(user.id),
     onSuccess: () => invalidateUserAccess(qc, user.id),
-    onError: () => notify({ level: "error", message: t("users.pendingAccess.activateFailed") }),
+    onError: (err) => notifyActionError(err, t("users.pendingAccess.activateFailed")),
   });
 
   const copy = async () => {