blake3 hashing code optimization

[akobrin1]

• moved blake3 hash enhancements from network-maker

• increased lukechampine.com/blake3 version from 1.4.0 to 1.4.1, 1.4.0 has serious bug that leads to incorrect hash calculation - "writing data in two calls where the first call ends exactly on a chunk boundary produced a wrong hash".

• unified all blake3-related hash functions in pkg/utils/hasher.go

• blake3 file hashing optimization:
  // hashReaderBLAKE3 computes a BLAKE3 hash using an adaptive,
  // manual buffered read loop to avoid the *os.File.WriteTo fast-path
  // that limits throughput when using io.Copy/io.CopyBuffer.
  //
  // The buffer size is chosen based on data size:
  //
  // ≤ 4 MiB → 512 KiB buffer
  // 4–32 MiB → 1 MiB buffer
  // 32 MiB–2 GiB → 2 MiB buffer
  // > 2 GiB → 4 MiB buffer
  //
  // Buffers are reused from a concurrent-safe pool to reduce allocations.
  // This approach achieved the following throughput in benchmarks
  // on AMD Ryzen 9 5900X (Linux, lukechampine.com/blake3):
  //
  // Data size | Adaptive | Manual(1MiB) | io.Copy(~32KiB)
  // ----------|-------------|--------------|----------------
  // 1 MiB | 1.80 GB/s | 1.26 GB/s | 0.52 GB/s
  // 32 MiB | 3.00 GB/s | 3.02 GB/s | 0.50 GB/s
  // 256 MiB | 3.79 GB/s | 3.35 GB/s | 0.48 GB/s
  // 1 GiB | 3.91 GB/s | 3.27 GB/s | 0.53 GB/s
  //
  // Compared to io.Copy/io.CopyBuffer, the adaptive manual loop is
  // up to ~7× faster on large files, with fewer allocations.

• added unit tests for all blake3 hashing functions

[Copilot]

Pull Request Overview

This PR consolidates BLAKE3 hashing functionality into a single location and optimizes file hashing performance. The key changes include:

• Upgrading lukechampine.com/blake3 from 1.4.0 to 1.4.1 to fix a critical hash calculation bug
• Consolidating BLAKE3 hash functions from pkg/utils/utils.go and pkg/crypto/hash.go into a new pkg/utils/hasher.go module
• Implementing adaptive buffer sizing for file hashing that achieves up to 7× performance improvement

Reviewed Changes

Copilot reviewed 10 out of 13 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
go.mod, cmd/sncli/go.mod, tests/system/go.mod	Updated blake3 dependency to v1.4.1
pkg/utils/hasher.go	New unified module with optimized BLAKE3 hashing functions
pkg/utils/hasher_test.go	Comprehensive test coverage for new hashing functions
pkg/utils/utils.go	Removed BLAKE3 functions (migrated to hasher.go)
pkg/crypto/hash.go	Deleted file (functionality moved to pkg/utils/hasher.go)
pkg/crypto/hash_test.go	Deleted file (tests moved to pkg/utils/hasher_test.go)
supernode/cascade/download.go, sdk/action/client.go	Updated to use new Blake3HashFile function

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Pull Request Overview

Copilot reviewed 10 out of 13 changed files in this pull request and generated 2 comments.

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Copilot reviewed 10 out of 13 changed files in this pull request and generated 1 comment.

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Pull Request Overview

Copilot reviewed 10 out of 13 changed files in this pull request and generated 2 comments.

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Pull Request Overview

Copilot reviewed 10 out of 13 changed files in this pull request and generated no new comments.

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