Add: Backup notification (#3225)

* Formatting updates

* Add: backup completion notification

* Fix: comment for backup

* Add: backup size units to notification

* Add: failed backup notification

* Add: calls to failed backup notification

* Update: notification OpenAPI spec

* Update notifications to first check if any are active for an event, update JS docs

---------

Co-authored-by: advplyr <advplyr@protonmail.com>

server/utils/notifications.js

@@ -27,6 +27,36 @@ module.exports.notificationData = {
         episodeDescription: 'Some description of the podcast episode.'
       }
     },
+    {
+      name: 'onBackupCompleted',
+      requiresLibrary: false,
+      description: 'Triggered when a backup is completed',
+      variables: ['completionTime', 'backupPath', 'backupSize', 'backupCount', 'removedOldest'],
+      defaults: {
+        title: 'Backup Completed',
+        body: 'Backup has been completed successfully.\n\nPath: {{backupPath}}\nSize: {{backupSize}} bytes\nCount: {{backupCount}}\nRemoved Oldest: {{removedOldest}}'
+      },
+      testData: {
+        completionTime: '12:00 AM',
+        backupPath: 'path/to/backup',
+        backupSize: '1.23 MB',
+        backupCount: '1',
+        removedOldest: 'false'
+      }
+    },
+    {
+      name: 'onBackupFailed',
+      requiresLibrary: false,
+      description: 'Triggered when a backup fails',
+      variables: ['errorMsg'],
+      defaults: {
+        title: 'Backup Failed',
+        body: 'Backup failed, check ABS logs for more information.\nError message: {{errorMsg}}'
+      },
+      testData: {
+        errorMsg: 'Example error message'
+      }
+    },
     {
       name: 'onTest',
       requiresLibrary: false,