Check component props for untranslated literals, and fail on a finding

i18n-literals checked title, aria-label, placeholder and alt on elements,
but not the same English passed to a component, so a MenuItem label or a
Popover ariaLabel written as a literal went through. It also excused a
literal that happened to be a catalogue key. That exemption is meant for
English held in a constant and translated where it renders, and a literal
written straight into a JSX attribute has no such render site. No
component passes its props through t(). And neither half of i18n:check
was run with --check, so a finding printed and the script still exited 0.

Component props are checked now, a key no longer excuses a literal in an
attribute, and both scripts run with --check. That found 28 strings
rendering English in every language: 19 already had keys and are wrapped,
and 9 are new keys in all nine catalogues. The contact editor's Save and
Saving… buttons are wrapped as well, on the same line.

package.json

@@ -23,7 +23,7 @@
     "dev:mock": "concurrently -n mock,server,web -c yellow,blue,magenta \"npm run mock -w server\" \"STALWART_URL=http://127.0.0.1:8788 npm run dev -w server\" \"npm run dev -w web\"",
     "dev:mock:no-future-release": "concurrently -n mock,server,web -c yellow,blue,magenta \"npm run mock:no-future-release -w server\" \"STALWART_URL=http://127.0.0.1:8788 npm run dev -w server\" \"npm run dev -w web\"",
     "i18n:coverage": "node scripts/i18n-coverage.mjs",
-    "i18n:check": "node scripts/i18n-catalog-check.mjs && node scripts/i18n-literals.mjs",
+    "i18n:check": "node scripts/i18n-catalog-check.mjs --check && node scripts/i18n-literals.mjs --check",
     "dev:mock:no-keyword-sort": "concurrently -n mock,server,web -c yellow,blue,magenta \"npm run mock:no-keyword-sort -w server\" \"STALWART_URL=http://127.0.0.1:8788 npm run dev -w server\" \"npm run dev -w web\""
   },
   "devDependencies": {