Add instructions for ordering PCBs with assembly to README

[Soundtoxin]

Thank you for Open-Frame1, it seems very exciting. I think the PCB ordering process is confusing for new users, so some additional info here would be a big help. The build guide video in the readme does not cover this part of the process. I'm hoping to build a few of these controllers and give some to friends in addition to using one myself if I can figure this out.

Something like you see in the README here would be good: https://github.com/rana-sylvatica/circle-keycaps

@rana-sylvatica has a detailed guide for getting some keycaps from JLC / jlcpcb.com in their README. I would like to use the same site to order some PCBs. The build guide video recommends having them solder on the USB-C port for you since that part is difficult, and possibly also the schottky diode while you're at it, but this process requires a BOM file and CPL file.
For the main target audience (gamers from the FGC) of these controllers, I think this will be difficult and initimidating. Many of them may not have dipped their toes into the DIY electronics world before now. The build guide video does a good job of being applicable to beginners by even recommending a starter soldering iron, solder, and other tools. If we can just improve the PCB ordering part of the process I think a lot more people would be able to actually build these controllers.

I understand that not everyone may order through JLC depending on their geography, but hopefully covering how to get a BOM and CPL file would be enough to help people using other sites as well, and JLC could just serve as an example.

[Soundtoxin]

I was also referred to the Phob guide for a different controller:

https://github.com/PhobGCC/PhobGCC-doc/blob/main/For_Makers/Phob2_Ordering_Guide.md

However for that controller they've supplied the needed files on their releases page for assembly, so they don't cover how else to get them, and the files would of course be different for the Frame1. I'm starting to get the feeling that the necessary knowledge to complete this is locked away in some Discord. As many people don't use Discord, it would be nice to have it out in the open with everything else.

[Soundtoxin]

I finally found that the needed files were in the repo, just not the releases page. I would recommend adding:
https://github.com/GregTurbo/Open-Frame1/blob/main/PCB/Board%20Fab%20Files/Open%20F1%20v1%20BOM%20(JLC).xlsx
https://github.com/GregTurbo/Open-Frame1/blob/main/PCB/Board%20Fab%20Files/Open%20F1%20v1%20CPL.xlsx

to the releases page similar to how PhobGCC provides the equivalent files on their releases page.

I'm also finding the process of having a case made rather confusing, but that might be outside the scope of this repo.

I have come across at least two options:
https://github.com/rana-sylvatica/OFOF1
and
https://www.thingiverse.com/thing:5445251

It's not totally clear how many parts actually need to be printed and put together and where to get them all. OFOF1 has standoffs and panels while the thingiverse has "Full_body" and "Full_backplate".
Again I think an additional guide is in order for just wrangling together all the parts and ordering them in the first place. In this case maybe both the above links are valid options, so they could just be explained better within the guide and clarify which parts you need to have printed to have a full enclosure in the end. My thoughts at this point are that I may just need to get most of what I think I need in-hand and then maybe during assembly I'll realize if something is missing, and then I'll end up waiting a few more days to get any parts I may be missing.
A guide could also discuss pros and cons of resin vs nylon for some of these parts and ways to make some things more affordable. I was a bit shocked at the shipping costs from JLC PCB (I'm in the US). For the PCBs I was paying almost exactly as much for shipping as I was for the boards. There were some cheaper shipping options but none significantly cheaper, so it didn't really seem worth a possible worse experience than DHL. To make matters worse, you can't order 3D prints and PCBs together from JLC, so I would have to eat that massive shipping cost a second time. I've held off ordering the 3D prints for now in case I can find a cheaper way to have those parts made (and because it's still unclear for sure which parts I do need to have made).

[Soundtoxin]

Just an update, the linked thingiverse case in the previous post has another (newer) variant that you can print at home in smaller pieces and then glue together. I've had mostly pretty good luck with using an Ender 3 v2 with PLA+ filament and then glueing with superglue. I would recommend this version as it can be printed without supports and is the most up-to-date version of the case.

https://www.thingiverse.com/thing:5632408