No, PD11 nor PD13 have a auto add clips that you've added to a working folder. However, what you can do since you have organized things so well into one working folder is simply:
1) While in PD a Ctrl+W (Import media folder)
2) migrate to your working folder and import it
3) New clips in the working folder that's being imported will be added to the PD media library. Any clips already present will still be there and not duplicated. Any clips that were used in the PD timeline will still have the green check in the upper right hand corner. If you also save your timeline *.pds file in the same working folder, no harm, it's not a valid media file(video, pic) so it's not imported.
Not exactly the auto feature you desire but maybe it will work for your needs.
Jeff