* llama: llama_prefetch_rows
* llama: support row prefetch on Windows
Apply the Windows port contributed by @praneshgo unchanged.
Source: https://github.com/ggml-org/llama.cpp/pull/29599#issuecomment-5887721014
* avoid exposing llama-mmap in model code, route via llama-impl
* add windows check, only prefetch in lazy mode
* cont : clean-up
* cont : fix build
* cont : clarify padding token for gemma4
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Co-authored-by: Pranesh Gonegandla <pranesh.iitp@gmail.com>
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>