Say the Archive folder needs the role, not the name

Archiving looks the folder up by its special-use role and by nothing else --
roleId("archive"), falling back to roleId("all") -- and then, finding
neither, told you to create a folder named "Archive". Naming a folder does
not give it a role, and ihasmail has no way to assign one: Folders settings
shows the role beside a folder and offers no way to set it. So the advice
sent someone round a loop that could not end. They make the folder, it still
does not work, and the message says the same thing again.

It now says what is actually required and where it lives: a folder needs the
Archive role on the server, and naming it "Archive" is not enough.

All nine catalogues carry the correction rather than falling back to English,
and they need the same native review the rest of them do.

The existing test asserted only that archiving complained. It now checks what
the complaint says, since the words were the whole bug.

Closes #217.

web/src/locales/nl.ts

@@ -955,7 +955,7 @@ export const catalog: Catalog = {
     "New all-day event on {date}": "Nieuwe hele dag durende afspraak op {date}",
     "New event at {time}": "Nieuwe afspraak om {time}",
     "New identity": "Nieuwe afzender",
-    "No Archive folder found. Create one named “Archive” first.": "Geen archiefmap gevonden. Maak er eerst een met de naam ‘Archive’.",
+    "No Archive folder is set. A folder needs the Archive role on the server; naming it “Archive” is not enough.": "Geen archiefmap ingesteld. Een map heeft op de server de rol ‘Archive’ nodig; die naam geven is niet genoeg.",
     "No contacts yet": "Nog geen contacten",
     "No longer shared": "Niet langer gedeeld",
     "No matches": "Geen overeenkomsten",