i18n DataGrid view-toggle tooltips

PR #4262 introduced a DataGrid view-toggle button with two hardcoded
English tooltip strings ("Switch to table view" / "Switch to card view")
and explicitly deferred translation to a follow-up. Without the keys in
the locale JSON files, next-intl would surface the raw label paths at
runtime for any non-English user once the strings move to t().

Adds switchToTableView and switchToCardView label entries in
messages.ts, swaps the hardcoded strings in DataGrid.tsx for
t(labels.x), and populates "switch-to-table-view" and
"switch-to-card-view" in all 52 locale JSON files with proper
translations (no English fallbacks).

Verified in Playwright that the toggle tooltip renders the expected
translated string in en-US, fr-FR and ja-JP via the same useMessages
pipeline already used for the search field placeholder, with no
MISSING_MESSAGE errors in the console.

public/intl/messages/fr-FR.json

@@ -310,6 +310,8 @@
     "sum": "Somme",
     "support": "Support",
     "switch-account": "Changer de compte",
+    "switch-to-card-view": "Passer à la vue cartes",
+    "switch-to-table-view": "Passer à la vue tableau",
     "table": "Tableau",
     "tablet": "Tablette",
     "tag": "Étiquette",