## Why
Some enterprise TLS proxies issue certificate chains signed with
`ecdsa_secp521r1_sha512` / `ECDSA_NISTP521_SHA512`. Custom CA
configuration such as `SSL_CERT_FILE` can add the right trust root, but
it cannot make `rustls`'s `ring` verifier support a certificate
signature algorithm it does not advertise.
That can still break TLS after the CA bundle is configured, including on
Rust websocket paths that call the shared
`ensure_rustls_crypto_provider()` helper, such as the Responses
websocket connector and remote app-server client:
-
[`codex-api/src/endpoint/responses_websocket.rs`](https://github.com/openai/codex/blob/eddc5c75ed527a8348bfcaa85692e53189600833/codex-rs/codex-api/src/endpoint/responses_websocket.rs#L441)
-
[`app-server-client/src/remote.rs`](https://github.com/openai/codex/blob/eddc5c75ed527a8348bfcaa85692e53189600833/codex-rs/app-server-client/src/remote.rs#L718)
The `aws-lc-rs` `rustls` provider supports this P-521/SHA-512
certificate signature scheme, so use it as Codex's process-wide `rustls`
provider.
## What Changed
- Switch the workspace `rustls` feature from `ring` to `aws_lc_rs`.
- Update `codex-utils-rustls-provider` to install
`rustls::crypto::aws_lc_rs::default_provider()`.
- Add an assertion and integration test that the installed provider
supports `ECDSA_NISTP521_SHA512`.
## Verification
```shell
just fmt
just test -p codex-utils-rustls-provider
just bazel-lock-update
just bazel-lock-check
```
## Summary
`cargo test` has entails both running standard Rust tests and doctests.
It turns out that the doctest discovery is fairly slow, and it's a cost
you pay even for crates that don't include any doctests.
This PR disables doctests with `doctest = false` for crates that lack
any doctests.
For the collection of crates below, this speeds up test execution by
>4x.
E.g., before this PR:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 1.849 s ± 4.455 s [User: 0.752 s, System: 1.367 s]
Range (min … max): 0.418 s … 14.529 s 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 428.6 ms ± 6.9 ms [User: 187.7 ms, System: 219.7 ms]
Range (min … max): 418.0 ms … 436.8 ms 10 runs
```
For a single crate, with >2x speedup, before:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 491.1 ms ± 9.0 ms [User: 229.8 ms, System: 234.9 ms]
Range (min … max): 480.9 ms … 512.0 ms 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 213.9 ms ± 4.3 ms [User: 112.8 ms, System: 84.0 ms]
Range (min … max): 206.8 ms … 221.0 ms 13 runs
```
Co-authored-by: Codex <noreply@openai.com>