Report the stale keys that are stale, and remove them

The check reported 41 stale keys per catalogue. Ten of them were.

The other 31 were strings held in constants and translated where they render --
t(b.description), t(group), t(c.label) -- so they reach t() as a variable and
there is no literal at the call site to find. The script already chased two of
those shapes, `label:` and objects named *_LABELS, with a comment about crying
wolf 33 times. The shapes kept coming: `description:` and `group:` on the
keyboard bindings, the calendar's view names, the read-receipt refusals, the
palette names.

Chasing them one at a time is the wrong shape of fix. Stale detection now asks
only "is this key still written down anywhere in the source" -- any string
literal counts. That under-reports, and that is the right way round: a missed
stale key costs a line of dead translation, a false one costs the credibility
of the check and every real finding after it. Which is what happened here --
these sat unread long enough to need a commit of their own.

Coverage keeps the strict set. The two questions need different nets, and
widening the one that measures what a catalogue *owes* would count every CSS
class and JMAP method name as an untranslated string -- it read 29% while I had
them sharing a set. `wanted` is the obligation, `seen` is the evidence.

What was actually dead, removed from all nine: "Availability on {date}",
"Import vCard", "PDF", two settings hints replaced by rewordings that are still
live, the Catppuccin palette description, and Tuesday through Friday -- left
behind when the week-start dropdown narrowed to the three days a week actually
starts on, and appearing since only in comments.

Coverage is unchanged at 1269/1285: none of the ten was ever owed.

web/src/locales/de.ts

@@ -327,7 +327,6 @@ export const catalog: Catalog = {
     "Busy": "Gebucht",
     "Free/busy": "Frei/Gebucht",
     "Show as": "Anzeigen als",
-    "Availability on {date}": "Verfügbarkeit am {date}",
     "Count all events as busy": "Alle Termine als gebucht zählen",
     "Only events I'm attending": "Nur Termine, an denen ich teilnehme",
     "Don't include in availability": "Nicht in die Verfügbarkeit einbeziehen",
@@ -366,7 +365,6 @@ export const catalog: Catalog = {
     "New address book": "Neues Adressbuch",
     "No address books yet.": "Noch keine Adressbücher.",
     "Choose from address books": "Aus Adressbüchern wählen",
-    "Import vCard": "vCard importieren",
     "Export all contacts": "Alle Kontakte exportieren",
     "Export address book": "Dieses Adressbuch exportieren",
     "Import contacts…": "Kontakte importieren…",
@@ -437,7 +435,6 @@ export const catalog: Catalog = {
     "Make ihasmail yours.": "Machen Sie ihasmail zu Ihrem.",
     "Reading": "Lesen",
     "Reading pane": "Lesebereich",
-    "Reading, sending and list behaviour. Settings are stored in this browser.": "Verhalten beim Lesen, Senden und in der Liste. Die Einstellungen werden in diesem Browser gespeichert.",
     "Right of the list": "Rechts von der Liste",
     "Below the list": "Unter der Liste",
     "Hidden (open full width)": "Ausgeblendet (in voller Breite öffnen)",
@@ -714,8 +711,6 @@ export const catalog: Catalog = {
     "Manage labels": "Labels verwalten",
     "Create “{name}”": "„{name}“ erstellen",
     "Type a name to create your first label.": "Geben Sie einen Namen ein, um Ihr erstes Label zu erstellen.",
-    "Labels are IMAP keywords stored on your messages, so they sync to other clients. Names and colours are kept in this browser.": "Labels sind IMAP-Schlüsselwörter, die in Ihren Nachrichten gespeichert werden und daher mit anderen Clients synchronisiert werden. Namen und Farben bleiben in diesem Browser.",
-    "PDF": "PDF",
     "Large attachments may be rejected by some servers": "Große Anhänge werden von manchen Servern abgelehnt",
     "Images are stored in your Files (folder “ihasmail”) and embedded when you send.": "Bilder werden in Ihren Dateien (Ordner „ihasmail“) gespeichert und beim Senden eingebettet.",
     "Thanks for your message. I'm away until … and will reply when I'm back.": "Vielen Dank für Ihre Nachricht. Ich bin bis … abwesend und melde mich nach meiner Rückkehr.",
@@ -839,16 +834,11 @@ export const catalog: Catalog = {
     "Drop here for the top level": "Hierher ziehen für die oberste Ebene",
 
     // ── Remaining prose ────────────────────────────────────────────────
-    "{name} is the palette from {site}, and what a new account starts on. It is a dark theme, so it counts as dark wherever that matters, and the accent colour below still applies on top of it.": "{name} ist die Farbpalette von {site} und das, womit ein neues Konto startet. Es ist ein dunkles Design und zählt daher überall dort als dunkel, wo das eine Rolle spielt; die Akzentfarbe unten wirkt weiterhin darauf.",
     "ihasmail's own version is the date of the commit it was built from, followed by where that commit came from: {example} was built from a commit dated the 30th of August 2026 that arrived through pull request 129. A commit that did not come through one carries its short SHA instead — {sha}. The version deliberately says nothing about Stalwart; what this build needs from the server is the line above.": "Die Version von ihasmail ist das Datum des Commits, aus dem es gebaut wurde, gefolgt davon, woher dieser Commit stammt: {example} wurde aus einem Commit vom 30. August 2026 gebaut, der über Pull Request 129 kam. Ein Commit, der nicht über einen solchen kam, trägt stattdessen seinen kurzen SHA — {sha}. Die Version sagt bewusst nichts über Stalwart aus; was dieser Build vom Server benötigt, steht in der Zeile darüber.",
 
     // ── Weekdays, schedule presets, rule operators ─────────────────────
     // Header names (List-Id, X-Spam-Status) stay English: they are the actual
     // field names in the message, not words.
-    "Tuesday": "Dienstag",
-    "Wednesday": "Mittwoch",
-    "Thursday": "Donnerstag",
-    "Friday": "Freitag",
     "Later today": "Später heute",
     "Tomorrow morning": "Morgen früh",
     "Tomorrow afternoon": "Morgen Nachmittag",