### What this PR does / why we need it?
To support elastic scaling when using mooncake connector, we should
support to **configure different tp sizes for different nodes**.
As a result, we transfer the prefill node information, such as tp size,
through **the request's kv_transfer_params**.
The decode nodes **get the prefill tp size** through the request's
kv_transfer_params, instead of getting it from the configuration of the
mooncake connector .
- vLLM version: v0.13.0
- vLLM main:
2f4e6548ef
Signed-off-by: yuxinshan <syx_ctyg@126.com>
Signed-off-by: CalvinXKY <kyxiezju@163.com>
0bb1f91c2c