Switch `ext/fetch` over to `resourceForReadableStream` to simplify and
unify implementation with `ext/serve`. This allows us to work in Rust
with resources only.
Two additional changes made to `resourceForReadableStream` were
required:
- Add an optional length to `resourceForReadableStream` which translates
to `size_hint`
- Fix a bug where writing to a closed stream that was full would panic
This is a prerequisite for fast streams work -- this particular resource
used a custom `mpsc`-style stream, and this work will allow us to unify
it with the streams in `ext/http` in time.
Instead of using Option as an internal semaphore for "correctly
completed EOF", we allow code to propagate errors into the channel which
can be picked up by downstream sinks like Hyper. EOF is signalled using
a more standard sender drop.
This commit reimplements most of "node:http" client APIs using
"ext/fetch".
There is some duplicated code and two removed Node compat tests that
will be fixed in follow up PRs.
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Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>