qwen4exp: fix sparse-attention block selection
Build QSA blocks per sequence in token order and select complete blocks
before expanding them to cache cells. Keep only the incomplete tail
unconditionally visible and rotate pooled keys with the first token's
full M-RoPE position.
This prevents unified-cache sequences from sharing pooled indexer keys
and avoids replacing padded tail entries with extra history tokens.
Synthetic Qwen4 architecture, exact mask, F16 and Q8_0 state,
sequence-copy, Metal, and AddressSanitizer checks pass.
Assisted-by: Codex
qwen4exp: support independent PLE embedding widths
Size the PLE key and value projections from the concatenated n-gram
embedding instead of assuming it matches the model hidden width.
Validate the head count before narrowing it to the stored type.
Add a synthetic PLE model with a 64-wide embedding and a 256-wide
hidden state, then verify inference and model roundtrip.
Assisted-by: Codex
qwen4exp: validate model metadata
Reject invalid GDN, hyper-connection, QSA, and PLE dimensions during
model loading instead of aborting later while building the graph.
Validate PLE array lengths before copying them into fixed storage.
The released configuration and synthetic Qwen4 architecture tests pass.
Assisted-by: Codex
qwen4exp: update indexer cache after sequence copies
Treat cached indexer keys as unrotated data and apply pending cache
updates alongside the attention and recurrent state. This copies indexer
data during non-unified cross-stream sequence copies without applying
RoPE shifts to raw keys.
Assisted-by: Codex
qwen4exp: enable recurrent state rollback
Assisted-by: Codex
qwen4exp: disable tensor split
Assisted-by: Codex
metal: align dynamic threadgroup memory
Assisted-by: Codex
metal: widen expert matmul thread index
Assisted-by: Codex
