perf(ext/node): use aws-lc-sys EVP API for chacha20-poly1305 (#33110)
## Summary
Replaces the hand-rolled ChaCha20 + Poly1305 implementation (using
RustCrypto `chacha20` + `poly1305` crates) with BoringSSL's streaming
`EVP_CIPHER` API via `aws-lc-sys`.
**Root cause of #33101**: The RustCrypto `chacha20` crate uses a
software-only backend on aarch64 (NEON requires an opt-in
`chacha20_force_neon` cfg flag), and the `poly1305` crate has **no
aarch64 SIMD backend at all**. This made `node:crypto` chacha20-poly1305
slower than pure-JS `@noble/ciphers` for payloads over ~4KB.
BoringSSL (`aws-lc`) provides hardware-accelerated implementations on
all platforms (NEON on aarch64, AVX2/SSE on x86_64). Since `aws-lc-sys`
is already a workspace dependency, this is a straightforward swap that
also removes two direct crate dependencies.
Closes #33101
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Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>