Example board modifications + final (hopefully) layouts

[ducky64]

Changes:

• Change diode drop of soft power gate to up to 0.6V, to allow JLC basic parts
• Move refdes prefixing into the netlist emitter. Add subboard prefix to the emitter, to allow unique nets under panelization.
• Add QMC5883P, which seems to have superseded the QMC5883L
• Add AMS1117, a JLC basic part LDO in SOT-223
• Update PNP fabdata for a bunch of parts
• Move the JLC PCBA postprocess script into a module, edg.utils.jlc_pcba, resolves Move jlc postprocess to vendor_parts.jlc #513
• Annotate basic part LEDs in comments.