Reapply "[MoE] [Refactor] Remove manual memory cleanup (#3365)" (#3483) (#3512)

### What this PR does / why we need it?
1. Replace manual memory cleanup with passing parameter.
2. FusedMoEPrepareAndFinalizeWithMC2 inherits All2All avoid duplicated
code.
3. Fix MC2 bug introduced in
https://github.com/vllm-project/vllm-ascend/pull/3365
4. Unify aclgraph & eager in W8A8_dynamic.
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?
e2e & ut

- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

Signed-off-by: Pr0Wh1teGivee <calvin_zhu0210@outlook.com>

tests/e2e/multicard/test_offline_inference_distributed.py

@@ -141,6 +141,7 @@ def test_models_distributed_Qwen3_W4A8DYNAMIC_new_version(model):
 
 @pytest.mark.parametrize("model", DEEPSEEK_W4A8_MODELS)
 @patch.dict(os.environ, {"VLLM_ASCEND_MLA_PA": "1"})
+@patch.dict(os.environ, {"HCCL_BUFFSIZE": "1024"})
 def test_models_distributed_DeepSeek_W4A8DYNAMIC(model):
     prompts = [
         "Hello, my name is",