best way to add a note to several records of custom entity (like bulk-edit) ?

Can someone tell me what architecture to use?

I want to be able to add to a Note ( Annotation) to several selected records  of my custom entity.

I have CRM 2011 on premise.

I’m fine with writing custom code -I just want to tip on where to do the code : in jquery, or a plugin , or a web resource page ?

Thanks, Peter