Modify STL Box With Hinged Lid

I already have the STL of a small rectangular box, but it needs a few functional tweaks before I can send it straight to the printer. I want a lid that prints in place together with the box, using built-in hinges so nothing has to be assembled afterwards. The closure will be a magnetic clasp, so please add recesses sized for common 6 mm × 2 mm disc magnets on both the lid and the mating face of the box.

All outside edges should be softened to a rounded profile so the part is comfortable to hold and less prone to chipping. The finished design must remain a single printable file; overhangs for the hinge pins are fine as long as standard FDM printers can handle them with minimal support. If you work in Fusion 360, SolidWorks, or similar, that’s ideal, but I ultimately need the final, watertight STL ready for slicing plus the source file in case I want to tweak dimensions later.

Before handing over the file, please sanity-check clearances for a typical 0.4 mm nozzle and 0.2 mm layer height (my usual setup). A quick screenshot or short video of the hinge movement in your CAD software would help confirm everything lines up.

Deliverables:
• Updated, print-in-place STL with hinged, magnet-ready lid
• Native CAD file (F3D, SLDPRT, STEP, or similar)
• Brief note on recommended slicer settings for the integrated hinges and magnet pockets