[lightning] save node features as stringified json array in db

backend/src/api/database-migration.ts

@@ -7,7 +7,7 @@ import cpfpRepository from '../repositories/CpfpRepository';
 import { RowDataPacket } from 'mysql2';
 
 class DatabaseMigration {
-  private static currentVersion = 63;
+  private static currentVersion = 64;
   private queryTimeout = 3600_000;
   private statisticsAddedIndexed = false;
   private uniqueLogs: string[] = [];
@@ -543,6 +543,11 @@ class DatabaseMigration {
       await this.$executeQuery('ALTER TABLE `blocks_audits` ADD fullrbf_txs JSON DEFAULT "[]"');
       await this.updateToSchemaVersion(63);
     }
+
+    if (databaseSchemaVersion < 64 && isBitcoin === true) {
+      await this.$executeQuery('ALTER TABLE `nodes` ADD features text NULL');
+      await this.updateToSchemaVersion(64);
+    }
   }
 
   /**