fix(settings): hold the channel test until changes are saved

The webhook, ntfy, email and Telegram test routes send through the
saved channel config. After a field changed, the card kept showing the
Saved note from the last save and Test still ran, so it reported on the
old settings: a webhook switched to the Gotify format was tested with
the generic body and Gotify refused it. The note now disappears on a
change, and the test button stays off with a save-first hint while the
form differs from what is saved. Refs #947

messages/de.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Verbindung testen",
+      "saveFirst": "Speichere zuerst deine Änderungen. Der Test nutzt die gespeicherten Einstellungen.",
       "testing": "Teste…",
       "ok": "Verbunden (Latenz {latency} ms)",
       "errors": {

messages/en.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Test connection",
+      "saveFirst": "Save your changes first. Test uses the saved settings.",
       "testing": "Testing…",
       "ok": "Connected (latency {latency} ms)",
       "errors": {

messages/es.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Probar conexión",
+      "saveFirst": "Guarda primero tus cambios. La prueba usa los ajustes guardados.",
       "testing": "Probando…",
       "ok": "Conectado (latencia {latency} ms)",
       "errors": {

messages/fr.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Tester la connexion",
+      "saveFirst": "Enregistrez d’abord vos modifications. Le test utilise les réglages enregistrés.",
       "testing": "Test en cours…",
       "ok": "Connecté (latence {latency} ms)",
       "errors": {

messages/it.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Prova connessione",
+      "saveFirst": "Salva prima le modifiche. La prova usa le impostazioni salvate.",
       "testing": "Test in corso…",
       "ok": "Connesso (latenza {latency} ms)",
       "errors": {

messages/ko.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "연결 테스트",
+      "saveFirst": "먼저 변경 사항을 저장해 주세요. 테스트는 저장된 설정을 사용해요.",
       "testing": "테스트 중…",
       "ok": "연결됨 (지연 {latency}ms)",
       "errors": {

messages/pl.json

@@ -6133,6 +6133,7 @@
     },
     "testConnection": {
       "test": "Testuj połączenie",
+      "saveFirst": "Najpierw zapisz zmiany. Test używa zapisanych ustawień.",
       "testing": "Testowanie…",
       "ok": "Połączono (opóźnienie {latency} ms)",
       "errors": {