Refactor error handling in FalukantService and enhance user feedback in HealthView

- Changed error throwing in FalukantService to use PreconditionError for better clarity.
- Added translations for "too close" error in both German and English locales.
- Improved user feedback in HealthView by displaying error messages in a dialog upon measure execution failure.

frontend/src/i18n/locales/de/falukant.json

@@ -918,6 +918,9 @@
             "success": "Erfolg",
             "selectMeasure": "Maßnahme",
             "perform": "Durchführen",
+            "errors": {
+                "tooClose": "Aktionen zu dicht hintereinander (maximal 1× pro 24 Stunden)."
+            },
             "measures": {
                 "pill": "Tablette",
                 "doctor": "Arztbesuch",