feat: add support for sync car reading

[hugomrdias]

This PR adds a new class CarReaderSync to support syncronous car reading.

Changes:

• Extracted some utils from the async decoder
  • decodeV2Header, decodeVarint and getMultihashLength
• Created a new sync decoder
• BytesReader interface has a new arg in the exactly method to seek after reading, defaults to false (previous behavior)
• Async decoder was tweaked to used the extracted utils and the new types.
• New types were added for buffer (sync) methods

I was hoping to be able to extract more from the async decoder than i did, but i think this is useful and does not introduce any breaking change.

The new CarReaderSync is exported in package.json.

[rvagg]

I'm not sure jsdoc2readme is working properly on this anymore, npm run docs is supposed to take the jsdoc updates and insert it into the readme; if that doesn't work, you might have to do a bit of manual sync, but getting something on the README would be good for this.

As long as the 3 of you agree on the details don't let me be a blocker, other than the desire for decent docs.

[hugomrdias]

I'm not sure jsdoc2readme is working properly on this anymore, npm run docs is supposed to take the jsdoc updates and insert it into the readme; if that doesn't work, you might have to do a bit of manual sync, but getting something on the README would be good for this.

As long as the 3 of you agree on the details don't let me be a blocker, other than the desire for decent docs.

i was able to make jsdoc2readme work readme is updated and i also added a reference to the sync reader in the usage section.

[hugomrdias]

@rvagg seems ready to merge.

[github-actions[bot]]

:tada: This PR is included in version 5.1.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: