Synchronized Editor: Store all events and allow multiple tabs

* This commit refactors the table used to store events.
* We also use a UUID as session identifier in the synchronized editor to support multiple concurrent tabs opened by the same user.
* Further, we renamed some methods to make them easier to distinguish.

db/migrate/20230906163923_rename_columns_in_events_synchronized_editor.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class RenameColumnsInEventsSynchronizedEditor < ActiveRecord::Migration[7.0]
+  def change
+    change_table :events_synchronized_editor do |t|
+      t.rename :action, :editor_action
+      t.rename :command, :action
+    end
+  end
+end