feat: Bytes-based public file writing API

[matheus23]

Previously we only had a CID-based API that just "set" the file CID to some value.

This now requires public files to encode their content as byte arrays.

Now the public and private APIs are very similar, both operate on the byte-array level for files.

Made possible through #375

TODO:

• Update Wasm bindings

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (main@ce292b5). Click here to learn what that means.
The diff coverage is 57.40%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #376   +/-   ##
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  Coverage        ?   53.86%           
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  Files           ?       55           
  Lines           ?     3891           
  Branches        ?      954           
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  Hits            ?     2096           
  Misses          ?     1182           
  Partials        ?      613           

Files	Coverage Δ
wnfs-common/src/async_serialize.rs	33.33% <ø> (ø)
wnfs-unixfs-file/src/balanced_tree.rs	80.48% <ø> (ø)
wnfs-unixfs-file/src/builder.rs	51.85% <ø> (ø)
wnfs-unixfs-file/src/chunker.rs	10.00% <100.00%> (ø)
wnfs-unixfs-file/src/chunker/fixed.rs	62.50% <100.00%> (ø)
wnfs-unixfs-file/src/types.rs	43.85% <ø> (ø)
wnfs/src/private/directory.rs	68.92% <ø> (ø)
wnfs/src/private/file.rs	73.68% <100.00%> (ø)
wnfs-unixfs-file/src/chunker/rabin.rs	0.00% <0.00%> (ø)
wnfs-unixfs-file/src/unixfs.rs	27.23% <0.00%> (ø)
... and 8 more