Function parse_trt_warmup_shapes 

pub(crate) fn parse_trt_warmup_shapes(
    raw: Option<String>,
) -> Vec<(usize, usize)>

Parses BGE_M3_TRT_WARMUP_SHAPES from its raw env-var value.

Accepts a comma-separated list of BxL tokens (e.g. "1x128,1x512"). Invalid tokens are skipped with a WARN. Returns the default shape set when raw is None, empty, or all tokens are invalid.