[Doc] Add 0.9.0rc1 release note

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>

Author: wangxiyuan

docs/source/user_guide/release_notes.md

@@ -1,5 +1,41 @@
 # Release note
 
+## v0.9.0rc1 - 2025.06.06
+
+This is the 1st release candidate of v0.9.0 for vllm-ascend. Please follow the [official doc](https://vllm-ascend.readthedocs.io/en/) to start the journey. From this release, V1 Engine is recommended to use. The code of V0 Engine is frozen and will not be maintained any more. Please set environment `VLLM_USE_V1=1` to enable V1 Engine.
+
+### Highlights
+
+- DeepSeek works with graph mode now. Follow the [official doc](https://vllm-ascend.readthedocs.io/en/latest/user_guide/graph_mode.html) to take a try. [#789](https://github.com/vllm-project/vllm-ascend/pull/789)
+- Qwen series models works with graph mode now. It works by defaut with V1 Engine. Please note that in this release, only Qwen series models are well tested with graph mode. We'll make it stable and generalize in the next release. If you hit any issues, please feel free to open an issue on GitHub and fallback to eager mode temporarily by set `enforce_eager=True` when initializing the model.
+
+### Core
+
+- The performance of multi-step scheduler has been improved. Thanks for the contribution from China Merchants Bank. [#814](https://github.com/vllm-project/vllm-ascend/pull/814)
+- prefix cache and chunked prefill feature works now [#782](https://github.com/vllm-project/vllm-ascend/pull/782) [#844](https://github.com/vllm-project/vllm-ascend/pull/844)
+- Spec decode and MTP features work with V1 Engine now. [#874]() [#890](https://github.com/vllm-project/vllm-ascend/pull/890)
+- DP feature works with DeepSeek now. [#1012](https://github.com/vllm-project/vllm-ascend/pull/1012)
+- Input embedding feature works with V0 Engine now. [#916](https://github.com/vllm-project/vllm-ascend/pull/916)
+- Sleep mode feature works with V1 Engine now. [#1084](https://github.com/vllm-project/vllm-ascend/pull/1084)
+
+### Model
+
+- Qwen2.5 VL works with V1 Engine now. [#736](https://github.com/vllm-project/vllm-ascend/pull/736)
+- LLama4 works now. [#740](https://github.com/vllm-project/vllm-ascend/pull/740)
+- A new kind of DeepSeek model called dual-batch overlap(DBO) is added. Please set `VLLM_ASCEND_ENABLE_DBO=1` to use it. [#941](https://github.com/vllm-project/vllm-ascend/pull/941)
+
+### Other
+
+- online serve with ascend quantization works now. [#877](https://github.com/vllm-project/vllm-ascend/pull/877)
+- A batch of bugs for graph mode and moe model have been fixed. [#773](https://github.com/vllm-project/vllm-ascend/pull/773) [#771](https://github.com/vllm-project/vllm-ascend/pull/771) [#774](https://github.com/vllm-project/vllm-ascend/pull/774) [#816](https://github.com/vllm-project/vllm-ascend/pull/816) [#817](https://github.com/vllm-project/vllm-ascend/pull/817) [#819](https://github.com/vllm-project/vllm-ascend/pull/819) [#912](https://github.com/vllm-project/vllm-ascend/pull/912) [#897](https://github.com/vllm-project/vllm-ascend/pull/897) [#961](https://github.com/vllm-project/vllm-ascend/pull/961) [#958](https://github.com/vllm-project/vllm-ascend/pull/958) [#913](https://github.com/vllm-project/vllm-ascend/pull/913) [#905](https://github.com/vllm-project/vllm-ascend/pull/905)
+- A batch of performance improvement PRs have been merged. [#784](https://github.com/vllm-project/vllm-ascend/pull/784) [#803](https://github.com/vllm-project/vllm-ascend/pull/803) [#966](https://github.com/vllm-project/vllm-ascend/pull/966) [#839](https://github.com/vllm-project/vllm-ascend/pull/839) [#970](https://github.com/vllm-project/vllm-ascend/pull/970) [#947](https://github.com/vllm-project/vllm-ascend/pull/947) [#987](https://github.com/vllm-project/vllm-ascend/pull/987) [#1085](https://github.com/vllm-project/vllm-ascend/pull/1085)
+- From this release, binary wheel package will be released as well. [#775](https://github.com/vllm-project/vllm-ascend/pull/775)
+- The contributor doc site is [added](https://vllm-ascend.readthedocs.io/en/latest/community/contributors.html)
+
+### Known Issue
+
+- In some case, vLLM process may be crashed with aclgraph enabled. We're working this issue and it'll be fixed in the next release.
+
 ## v0.7.3.post1 - 2025.05.29
 
 This is the first post release of 0.7.3. Please follow the [official doc](https://vllm-ascend.readthedocs.io/en/v0.7.3-dev) to start the journey. It includes the following changes: