* Make `ServeDir` infallible

* add missing docs

* depend on tracing for `fs`

* add note about requiring infallible fallbacks

* clean up

* format

* Implement require_auth with validate_request

* Update CHANGELOG

* Fix style

* Address comments

Signed-off-by: Daniele Ahmed <ahmeddan@amazon.de>

Signed-off-by: Daniele Ahmed <ahmeddan@amazon.de>

This updates base64 to the latest version.

* Don't include identity in Content-Encoding header

According to the [spec][1] `identity` should only be used for the
Accept-Encoding header and not be included in Content-Encoding.

In practice this change fixes chunked video loading in Firefox when
using `ServeDir`. (making seeking possible without downloading the whole
video file)

[1]: https://httpwg.org/specs/rfc9110.html#field.content-encoding

* Address review comment

* Add test for `Accept-Encoding: identity`

* Still compress svgs

Even though they're images they're really just xml, so should still be
compressed.

Fixes #320

* changelog

* ServeDir: convert io::ErrorKind::NotADirectory to not_found

* only check raw OS error on unix OS, add comment.

* mention "is a directory" handling in ServeDir in documentation

* Support zstd compression

* fix

* Give zstd highest priority for `accept-encoding`

* fix typo

* Use `.zst` extension for files precompressed with zstd

* don't pull in two `zstd`s

* This allows interop with `tonic::transport::Server` and `tonic::transport::server::Router::serve_with_shutdown` which require that the responses implement `Default`.

* Add layer to decompress request bodies

Still needs some refactor to remove duplicate code and needs documentation

* Refactor decompression modules

* Fix incorrect rename

* Add ResponseFuture for RequestDecompression

Which either polls its inner future or returns 415 Unsupported Media Type

* Refactor DecompressionService

* Rollback rename and move of `Decompression`

Refactoring of `decompression` module will be done in a later PR

* Re-add `request` module to the `decompression` module

* Send "identity" encoding when no encodings are accepted

* Add documentation

* Add example

* Fix styling

* Fix some styling of imports and documentation

* Add enable parameter to RequestDecompressionLayer::pass_through_unaccepted

* Cleanup redundant code

* fix imports

* actually fix import

* check for zstd

* zstd

---------

Co-authored-by: David Pedersen <david.pdrsn@gmail.com>

* Release 0.4.0

:rocket:

* add zstd to changelog