[Glm46v] Bug fix for accuracy drop and unable to launch server (#14585)

Co-authored-by: yhyang201 <yhyang201@gmail.com>
Co-authored-by: zRzRzRzRzRzRzR <2448370773@qq.com>
Co-authored-by: Minglei Zhu <mingleizhu1122@gmail.com>

docs/basic_usage/glm45.md

@@ -0,0 +1,70 @@
+## Launch GLM-4.5 / GLM-4.6 with SGLang
+
+To serve GLM-4.5 / GLM-4.6 FP8 models on 8xH100/H200 GPUs:
+
+```bash
+python3 -m sglang.launch_server --model zai-org/GLM-4.6-FP8 --tp 8
+```
+
+### Configuration Tips
+
+- `--max-mamba-cache-size`: Adjust `--max-mamba-cache-size` to increase mamba cache space and max running requests
+  capability. It will decrease KV cache space as a trade-off. You can adjust it according to workload.
+
+### EAGLE Speculative Decoding
+
+**Description**: SGLang has supported GLM-4.5 / GLM-4.6 models
+with [EAGLE speculative decoding](https://docs.sglang.io/advanced_features/speculative_decoding.html#EAGLE-Decoding).
+
+**Usage**:
+Add arguments `--speculative-algorithm`, `--speculative-num-steps`, `--speculative-eagle-topk` and
+`--speculative-num-draft-tokens` to enable this feature. For example:
+
+``` bash
+python3 -m sglang.launch_server \
+  --model-path zai-org/GLM-4.6-FP8 \
+  --tp-size 8 \
+  --tool-call-parser glm45  \
+  --reasoning-parser glm45  \
+  --speculative-algorithm EAGLE \
+  --speculative-num-steps 3  \
+  --speculative-eagle-topk 1  \
+  --speculative-num-draft-tokens 4 \
+  --mem-fraction-static 0.9 \
+  --served-model-name glm-4.6-fp8 \
+  --enable-custom-logit-processor
+```
+
+### Thinking Budget for GLM-4.5 / GLM-4.6
+
+In SGLang, we can implement thinking budget with `CustomLogitProcessor`.
+
+Launch a server with `--enable-custom-logit-processor` flag on.
+
+Sample Request:
+
+```python
+import openai
+from rich.pretty import pprint
+from sglang.srt.sampling.custom_logit_processor import Glm4MoeThinkingBudgetLogitProcessor
+
+
+client = openai.Client(base_url="http://127.0.0.1:30000/v1", api_key="*")
+response = client.chat.completions.create(
+    model="zai-org/GLM-4.6",
+    messages=[
+        {
+            "role": "user",
+            "content": "Question: Is Paris the Capital of France?",
+        }
+    ],
+    max_tokens=1024,
+    extra_body={
+        "custom_logit_processor": Glm4MoeThinkingBudgetLogitProcessor().to_str(),
+        "custom_params": {
+            "thinking_budget": 512,
+        },
+    },
+)
+pprint(response)
+```