//! GPU forward path for a Qwen3-style decoder using `wgpu` compute pipelines.
//!
//! Design notes:
//! - Decoder weights live in persistent GPU buffers created once in `GpuModelState::new()`.
//! - Embedding gather is performed on CPU and uploaded as one dense hidden-state
//! buffer per call (sparse embedding lookup stays host-side).
//! - `runtime.max_seq_len` is a practical attention allocation cap. This implementation
//! materializes an explicit `[num_heads, seq, seq]` score buffer (not flash-attention).
pub use ;