chore: remove flat-head

[suchapalaver]

Removing flat-head to prioritize releasing a library for pre-merge verifiable extraction. It provides an interesting example of using our decoder and header accumulator crates, but it's essentially an app that uses them rather than a logical part of the library.

We do have ideas to use the S3 interface in the decoder Reader:

• https://linear.app/semiotic/issue/BACK-142/add-s3-support-to-flat-files-decoder
• https://linear.app/semiotic/issue/BACK-144/generic-retrieval-of-flat-files

[linear]

BACK-141 remove `flat-head` from `veemon`

joseph said in BACK-72:

I suggest we remove flat-head from veemon. We should archive the code somewhere as it might have some useful solutions for specific user cases such as S3 buckets. We could make another example out of the code.

We should make flat-head a private repo in semiotic-ai in case we want to use any of the store solutions.

[pedrohba1]

The Store approach seems to make more sense, just to clarify it would be based on the store.rs that was on flat_head.

[suchapalaver]

The Store approach seems to make more sense, just to clarify it would be based on the store.rs that was on flat_head.

I think we're talking about the same thing.