Type-Check CID

[appcypher]

Summary

This PR implements the following features

• Type-checks CID for better error message

cids have been updated to use the multiformat-based CID class but old code still use string encoded formats which leads to vague errors. This PR adds a check that returns a clear error message when a cid parameter isn't an object.

Closing issues

Fixes #345

[matheus23]

I'm sorry for throwing you into JS/TS land which is horrible :P

instanceof is dangerous in JS, because if for whatever reason you'll end up with a duplicated copy of the multiformats library in your bundle, their CID classes are not instanceof-compatible with each other.

Here's an issue comment that shows the desired pattern to use instead: multiformats/js-cid#111 (comment)

I know, this is an annoyingly small thing and you want to get working on something bigger, it's just for you to get familiar with different parts of our toolchain + code. (Almost done 🎉)

[appcypher]

No. It's fine. You have been really helpful. 😀

[appcypher]

For context and as discussed with @icidasset, the error we get comes from CID being sent via postMessage to a decoding piece that assumes CIDs are of CID class instance (not strings). So the ideal place to do a check is right before the CID is sent since there are other areas in the code that handle a CID multiform nature.

[matheus23]

Can we make this cid = typeCheckCID(cid), where typeCheckCID returns what CID.asCID returns if its non-falsy?
This way we're automatically converting between a couple of CID types in some edge cases.

[appcypher]

Good to go? @icidasset @matheus23

[icidasset]

[matheus23]

🎉