[Doc][v0.18.0] Fix documentation formatting and improve code examples (#8701)

### What this PR does / why we need it?
This PR fixes various documentation issues and improves code examples
throughout the project.

Signed-off-by: MrZ20 <2609716663@qq.com>

tests/e2e/multicard/2-cards/test_qwen3_moe.py

@@ -80,7 +80,7 @@ async def test_qwen3_moe_w8a8_distributed_tp2_ep_dynamic_eplb():
     port = get_open_port()
     compilation_config = json.dumps({"cudagraph_capture_sizes": [8]})
     server_args = [
-        "--max_model_len",
+        "--max-model-len",
         "8192",
         "--tensor_parallel_size",
         "2",

tests/e2e/nightly/single_node/models/scripts/GUIDE_AND_TEMPLATE.md

@@ -239,7 +239,7 @@ test_cases:
       <<: *envs
     server_cmd: *server_cmd
     benchmarks:
-      <<: *benchmarks_acc
+      <<: *benchmarks
 ```
 
 #### EPD / Disaggregated Case

tests/e2e/run_doctests.sh

@@ -21,7 +21,7 @@ set -eo errexit
 
 . $(dirname "$0")/common.sh
 
-export VLLM_USE_MODELSCOPE=true
+export VLLM_USE_MODELSCOPE=True
 export MODELSCOPE_HUB_FILE_LOCK=false
 export HF_HUB_OFFLINE=1