chore: update database migration

db/migrate/20250512102319_remove_old_indexes_from_messages.rb

@@ -0,0 +1,11 @@
+class RemoveOldIndexesFromMessages < ActiveRecord::Migration[7.0]
+  def up
+    remove_index :messages, name: 'index_messages_on_content', if_exists: true
+    remove_index :messages, name: 'index_messages_on_source_id', if_exists: true
+  end
+
+  def down
+    add_index :messages, :content, using: :gin, opclass: :gin_trgm_ops, name: 'index_messages_on_content' unless index_exists?(:messages, :content, name: 'index_messages_on_content')
+    add_index :messages, :source_id, name: 'index_messages_on_source_id' unless index_exists?(:messages, :source_id, name: 'index_messages_on_source_id')
+  end
+end