fix(ci): remove conflicting BLAKE3 feature flags

Remove `simd-neon` and `pure` feature flags from wraith-files/Cargo.toml
that conflict when CI runs with `--all-features`. BLAKE3 automatically
detects and uses the best available SIMD instructions, so explicit
feature flags are unnecessary and cause build failures.

- Remove simd-neon feature (auto-enabled on aarch64)
- Remove pure feature (conflicts with SIMD features)
- Keep rayon feature for multi-threading
- Update tree_hash.rs documentation to match

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: doublegate

crates/wraith-files/Cargo.toml

@@ -9,23 +9,11 @@ repository.workspace = true
 authors.workspace = true
 
 [features]
-# SIMD acceleration features for BLAKE3 hashing
-# Enable the appropriate feature for your target platform for maximum performance
-
-# Default: Rayon multi-threading + SIMD (auto-detected by blake3)
-default = ["rayon"]
-
-# Multi-threading with rayon (recommended for all platforms)
+# BLAKE3 multi-threading with rayon (recommended for all platforms)
 # BLAKE3 automatically uses SIMD (AVX2, AVX-512, NEON) based on target CPU
+default = ["rayon"]
 rayon = ["blake3/rayon"]
 
-# ARM NEON SIMD (auto-enabled on aarch64, 2-4x speedup on ARM)
-# Note: NEON is automatically enabled on aarch64; this feature is for explicit control
-simd-neon = ["blake3/neon"]
-
-# Pure Rust implementation (no SIMD, for compatibility)
-pure = ["blake3/pure"]
-
 [dependencies]
 wraith-core = { workspace = true }
 wraith-crypto = { workspace = true }

crates/wraith-files/src/tree_hash.rs

@@ -15,8 +15,6 @@
 //!
 //! - `default`: Rayon multi-threading + automatic SIMD detection (recommended)
 //! - `rayon`: Multi-threaded hashing across cores
-//! - `simd-neon`: Explicit ARM NEON SIMD (auto-enabled on aarch64)
-//! - `pure`: Pure Rust implementation without SIMD (for compatibility)
 //!
 //! ## SIMD Support
 //!
@@ -39,22 +37,13 @@
 //! wraith-files = { version = "*", features = ["rayon"] }
 //! ```
 //!
-//! **Pure Rust (no SIMD):**
-//! ```toml
-//! wraith-files = { version = "*", features = ["pure"] }
-//! ```
-//!
 //! ## Performance
 //!
-//! With SIMD acceleration enabled:
+//! With SIMD acceleration (automatic):
 //! - **File hashing**: >3 GiB/s (in-memory), >1.5 GiB/s (from disk)
 //! - **Chunk verification**: <1 μs per 256 KiB chunk
 //! - **Incremental hashing**: >2 GiB/s (streaming)
 //!
-//! Without SIMD (software-only):
-//! - **File hashing**: ~800 MiB/s
-//! - **Chunk verification**: ~3 μs per chunk
-//!
 //! SIMD provides a 2-4x speedup on most platforms, with AVX-512 reaching
 //! up to 8x on supported hardware.