[Model] Make the dummy-run recipe feature-neutral

Per review, the warmup recipe is a property of the model's request
geometry, not of distributed layerwise offload: rename
dlo_dummy_run_recipe to dummy_run_recipe and drop the DLO gate in
_make_dummy_request. A model whose geometry needs recipe-specific sampling
arguments warms up at startup whatever features are enabled — under DLO
the generation also primes the component cache-retention budget; without
it, the same warmup covers any other first-request cost. Validated both
ways on L20X: DLO boot unchanged (releases stay in the startup window) and
a non-DLO MiniMax-H3 boot now runs the warmup and serves normally.

Signed-off-by: hsliuustc0106 <liuhongsheng4@huawei.com>

docs/user_guide/diffusion/offloader/distributed_layerwise_offload.md

@@ -69,13 +69,13 @@ omni = Omni(
 
 ## Startup warmup
 
-Under DLO, models that need model-specific sampling arguments for a warmup
-generation (currently MiniMax-H3: `t2va`, an explicit aspect ratio) run one
-at engine startup. It runs at the maximum output duration so the component
-allocator-cache retention policy learns a footprint that covers every
-production request: the cold-start flushes happen during startup and no real
-request pays them. The tradeoff is one maximum-length generation added to
-boot time; on deployments without DLO the behavior is unchanged.
+Models whose request geometry needs model-specific sampling arguments for a
+warmup generation (currently MiniMax-H3: `t2va`, an explicit aspect ratio)
+run one at engine startup whatever features are enabled. It runs at the
+maximum output duration so it covers every production request; under DLO
+this means the component allocator-cache retention policy learns its
+footprint during startup and no real request pays the cold-start flushes.
+The tradeoff is one maximum-length generation added to boot time.
 
 ## Host-weight loading