Function normalize_batch_parallel 

pub fn normalize_batch_parallel(data: &mut [f32], dim: usize) -> Vec<f32>

Parallel batch L2 normalization using SIMD and multi-threading.

This is the high-performance version for processing thousands of vectors. Uses rayon for parallelism and SIMD for per-vector operations.

Arguments

• data - Flat array of vectors stored contiguously
• dim - Dimension of each vector

Returns

Vector of original norms for each vector.

Performance

• Uses rayon for parallel processing across CPU cores
• Uses SIMD (AVX2 on x86_64) for individual vector operations
• Optimal for batches of 1000+ vectors