Say every Administration refusal in the reader's language

Stalwart explains a refused change in English, and several of its words
reached the page as they were: "Invalid domain name" for a reserved TLD,
"Invalid email address" for a catch-all, a grant refusal, and ihasmail's own
proxy messages. Every registry error type now has its own message, and a
value one of the registry's string validators refused is recognised by the
validator's wording and explained again. A domain clash or a missing domain
is worded for a domain rather than an account.

The one exception is kept on purpose: a password policy's reason follows a
translated sentence, because the rule is the server's and dropping it would
leave no way to find out why.

The mock now refuses a reserved TLD and a catch-all without a domain the way
the live server did. KNOWN-ISSUES records the fix, and that the last two live
cases -- an administrator-set password and the outranking guard -- held.

15 new strings in all nine catalogues, 3 retired; strings falling back to
English stay at 16.

web/src/views/admin/DomainSheet.tsx

@@ -98,7 +98,7 @@ export function DomainSheet({ id, accountCount, onClose, onChanged, onCreated, o
           void namesOf("DnsServer", [serverId]).then((n) => { if (!cancelled) setProvider(n.get(serverId) ?? null); }, () => {});
         }
       } catch (err) {
-        if (!cancelled) setLoadError(describeDirectoryError(err));
+        if (!cancelled) setLoadError(describeDirectoryError(err, "domain"));
       }
     })();
     return () => {
@@ -148,7 +148,7 @@ export function DomainSheet({ id, accountCount, onClose, onChanged, onCreated, o
       setRevision((n) => n + 1);
       onChanged();
     } catch (err) {
-      setError(describeDirectoryError(err));
+      setError(describeDirectoryError(err, "domain"));
     } finally {
       setBusy(false);
     }
@@ -389,7 +389,7 @@ function RemoveDomain({ domain, accountCount, keys, canRemoveKeys, onDeleted }:
                   setError(
                     err instanceof DomainError && err.type === "objectIsLinked" && err.linked.length
                       ? t("The server kept the domain: it is still used by {things}.", { things: describeLinked(err.linked) })
-                      : describeDirectoryError(err),
+                      : describeDirectoryError(err, "domain"),
                   );
                 } finally {
                   setBusy(false);

web/src/views/admin/DomainsAdmin.tsx

@@ -47,7 +47,7 @@ export function DomainsAdmin({ selectedId }: { selectedId?: string }) {
       } catch (err) {
         if (!cancelled) {
           setPage({ domains: [], total: 0 });
-          setError(describeDirectoryError(err));
+          setError(describeDirectoryError(err, "domain"));
         }
       }
     })();