Merge the wasi-tls crates into a single one with feature flags (#12780)

prtest:full

wasi-tls: Add OpenSSL backend (#12228)

* Create an OpenSSL backend for wasi-tls

* vet wasmtime-wasi-tls-openssl

* Add more vets

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Co-authored-by: Alex Crichton <[email protected]>

docs: Add an example application that embeds Wasmtime in order to use plugins (#11848)

* docs: Add an example application that embeds Wasmtime in order to use plugins

* Add exact version to clap de

docs: Add an example application that embeds Wasmtime in order to use plugins (#11848)

* docs: Add an example application that embeds Wasmtime in order to use plugins

* Add exact version to clap dependency

* Re-generate Cargo.lock

* Address review feedback

* Refactor args structs

* Address further review comments

* Exclude calculator example from `cargo doc` in CI

show more ...

Add `native-tls` backend for wasi-tls (#11064)

* Reorganize the wasi-tls folder and isolate the `rustls`-specific bits from the rest of the implementation.
- `client.rs`: The rustls parts.
- `io.rs`

Add `native-tls` backend for wasi-tls (#11064)

* Reorganize the wasi-tls folder and isolate the `rustls`-specific bits from the rest of the implementation.
- `client.rs`: The rustls parts.
- `io.rs`: WASI I/O conversion utility types.
- `host.rs`: The host types + impls.
- `bindings.rs`: The generated bindings.

* Add `native-tls` backend

* Improve compatibility of `test_tls_sample_application`:
It used to perform a "half-close" after sending the HTTP request. This is a TLS1.3+ feature, though Rustls & OpenSSL already supported it for TLS1.2 and lower. Technically, that makes them non-spec compliant, but they chose to align with the semantics of the underlying TCP connection. I suspect the TLS1.3 spec was updated to match what was already happening in reality.
Anyhow, SChannel does not support half-closed connections and so the `read` call after the `close_output+shutdown` failed.
I've reordered the test to first perform the HTTP conversation and _then_ do the TLS+TCP teardown.

* Implement flushing on the `AsyncWriteStream`. The `AsyncWriteStream` implementation was copied from the TCP equivalent, which doesn't need flushing. The TLS implementations _do_ maintain an internal buffer, so the `flush` call need to be hooked up.

* Switch to a model that uses runtime configuration.

* Check wasmtime-wasi-tls features in isolation.

* Clarify intended use of `WasiTlsCtxBuilder::provider`

* Split off native-tls implementation into separate crate

* Add a dedicated Ci job to test the `native-tls` backend.

prtest:full

* Update vets

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Co-authored-by: Alex Crichton <[email protected]>

show more ...

Migrate run-tests.sh to Python (#10790)

* Migrate run-tests.sh to Python

Try to fix MinGW breakage in CI

prtest:full

* Use python shell

* Try again

* Exit Python with the same code as Cargo