Say which legacy protocols are off when only some are

inbuxa can now switch IMAP, POP3 and ManageSieve off one at a time,
server-wide and per organization, and the session lists what is still
allowed for the account (legacyAllowed). Where the webmail said
"legacy protocols are off", it now also covers the case where only
some are:

- Security & sessions, above app passwords: "Your organization has
  turned off POP3 for mail apps. Mail apps that use it can't connect
  to this account; others still can."
- The Administration dashboard: "Some legacy mail protocols are off for
  your organization: POP3."
- An organization's sheet in Administration: its switch stays the
  all-or-nothing one; when only some are off it names them and points
  to the console, where they're switched one at a time, and "Turn
  legacy protocols back on" turns them all back on.

With every protocol off, the existing wording shows, as before. From a
server that doesn't send legacyAllowed nothing new appears.

3 new strings in all nine catalogs, unreviewed.

Tested: unit tests for reading the session and a tenant's switches;
the existing tests updated for the new field; typecheck; the whole
suite (1475 tests); and in headless Chrome against a local server with
POP3 off, where Security & sessions showed the new note.

web/src/locales/de.ts

@@ -1754,6 +1754,10 @@ export const catalog: Catalog = {
     // ── Spam filter: the language model's opinion (inbuxa) ──────────
     "Language model's opinion": "Einschätzung des Sprachmodells",
     "One of several signals the spam filter weighed": "Eines von mehreren Signalen, die der Spamfilter berücksichtigt hat",
+    // inbuxa: legacy mail protocols, one switch per protocol
+    "Your organization has turned off {protocols} for mail apps. Mail apps that use it can't connect to this account; others still can.": "Ihre Organisation hat {protocols} für Mail-Apps ausgeschaltet. Mail-Apps, die das nutzen, können sich nicht mit diesem Konto verbinden; andere schon.",
+    "Some legacy mail protocols are off for your organization: {protocols}.": "Einige ältere Mailprotokolle sind für Ihre Organisation ausgeschaltet: {protocols}.",
+    "Some are off for {tenant}: {protocols}. Switch them one at a time in the administration console.": "Einige sind für {tenant} aus: {protocols}. In der Verwaltungskonsole lassen sie sich einzeln ein- und ausschalten.",
     // inbuxa: deleting a person is the console's (audit-hold-lock spec)
     "Deleting, locking and legal holds are done in the administration console, which records why and keeps what a hold covers.": "Löschen, Sperren und rechtliche Aufbewahrungspflichten werden in der Verwaltungskonsole erledigt, die den Grund festhält und bewahrt, was eine Aufbewahrungspflicht umfasst.",
     "Open in the console": "In der Konsole öffnen",