feat: add SMS diagnostics admin check

frontend/src/types.ts

@@ -48,6 +48,17 @@ export interface Watcher1Settings {
   contact: string;
 }
 
+export interface SmsDiagnosticsResult {
+  provider: string;
+  url: string;
+  ok: boolean;
+  reachable: boolean;
+  httpStatus: number | null;
+  elapsedMs: number;
+  checkedAt: string;
+  error: string | null;
+}
+
 export interface Team {
   id: number;
   code: string;