Run some sanity checks/validations on the private key input. Cannot save it unless the field is valid.

Shared (Extension)/Resources/utils.js

@@ -206,3 +206,10 @@ export function humanPermission(p) {
             return 'Unknown';
     }
 }
+
+export function validateKey(key) {
+    const hexMatch = /^[\da-f]{64}$/i.test(key);
+    const b32Match = /^nsec1[qpzry9x8gf2tvdw0s3jn54khce6mua7l]{58}$/.test(key);
+
+    return hexMatch || b32Match;
+}