Add a new "Flag for Bulk" Action (available on an individual record or the index view) to store (via the User Preferences API, CO-1928) an indicator that a record should be processed in the next bulk action.

The actual bulk request will be queued via a "Process Bulk" action on supported index views, which then presents a page to specify which bulk action is desired (including a "Clear All Bulk Flags" action). The action will then be queued for the BulkJob command (CO-2087) to process (or maybe there's a "process synchronously" option the admin can select for smaller operations).