Update MaxText version to v0.2.2 and add release notes.

PiperOrigin-RevId: 912602689

Author: SurbhiJainUSC

docs/release_notes.md

@@ -22,8 +22,37 @@ MaxText is [available in PyPI](https://pypi.org/project/maxtext/) and can be ins
 
 ## Releases
 
+### v0.2.2
+
+#### Changes
+
+- Upgraded JAX to version 0.9.2, improving support for both pre-training and post-training.
+- Introduced simplified APIs for accessing MaxText models.
+- Included [maxtext_with_gepa.ipynb](https://github.com/AI-Hypercomputer/maxtext/blob/3c7d8d27864fc12cccac07786f02bd0e5262c982/src/maxtext/examples/maxtext_with_gepa.ipynb), a new notebook demonstrating AIME prompt optimization using the GEPA framework within MaxText.
+- Added support for Kimi-K2 models and the MuonClip optimizer. Users can explore this with the [kimi-k2-1t](https://github.com/AI-Hypercomputer/maxtext/blob/fa5b5ebf9a8e4f7a33bd88eae051dc21f3147791/src/maxtext/configs/models/kimi-k2-1t.yml) config (see [user guide](https://github.com/AI-Hypercomputer/maxtext/blob/fa5b5ebf9a8e4f7a33bd88eae051dc21f3147791/tests/end_to_end/tpu/kimi/Run_Kimi.md) for details).
+- Kimi-K2-Thinking, Kimi-K2.5 (text), and Kimi-K2.6 (text) are now supported. See [Run_Kimi.md](https://github.com/AI-Hypercomputer/maxtext/blob/main/tests/end_to_end/tpu/kimi/Run_Kimi.md#quantized-variants-k2-thinking-k25-k26) for details.
+- [DeepSeek-V3.2](https://arxiv.org/pdf/2512.02556) is now supported, including DeepSeek Sparse Attention for handling long contexts. Use the [deepseek3.2-671b](https://github.com/AI-Hypercomputer/maxtext/blob/20d93f62a91899dbbb8f23562973d75104411d3a/src/maxtext/configs/models/deepseek3.2-671b.yml) config to try it out (refer to the [user guide](https://github.com/AI-Hypercomputer/maxtext/blob/20d93f62a91899dbbb8f23562973d75104411d3a/tests/end_to_end/tpu/deepseek/Run_DeepSeek.md) for more information).
+- Support has been added for Gemma 4 multi-modal models (26B MoE and 31B dense). These can be used with the [gemma4-26b](https://github.com/AI-Hypercomputer/maxtext/blob/cdc587f0935a5e2d6f8287b96669cf2e87a0acdc/src/maxtext/configs/models/gemma4-26b.yml) and [gemma4-31b](https://github.com/AI-Hypercomputer/maxtext/blob/cdc587f0935a5e2d6f8287b96669cf2e87a0acdc/src/maxtext/configs/models/gemma4-31b.yml) configs. See [Run_Gemma4.md](https://github.com/AI-Hypercomputer/maxtext/blob/cdc587f0935a5e2d6f8287b96669cf2e87a0acdc/tests/end_to_end/tpu/gemma4/Run_Gemma4.md) for further details.
+- Support has been added for Gemma 4 inference using [MaxText on vLLM plugin](https://maxtext.readthedocs.io/en/maxtext-v0.2.2/tutorials/inference.html).
+- Enhanced RL capabilities with support for the `open-r1/OpenR1-Math-220k` dataset and `nvidia/OpenMathReasoning`.
+- Added more evaluation modes for RL like majority voting and pass@1 estimation.
+- Sync weights to vllm prior to pre RL evaluation.
+- More robust usage of math-verify in RL.
+- MaxText's Supervised Fine-Tuning (SFT) now supports non-instruct models.
+- Added support for tensor parallelism using the Fused MoE kernel for MaxText on vLLM inference.
+- Added support for MaxText to vllm converters for Qwen3 and Gemma4 family of models.
+- [validate_converter.py](https://github.com/AI-Hypercomputer/maxtext/blob/472f53b70089e661be399ad3905c05a53a172ec5/src/maxtext/integration/vllm/torchax_converter/validate_converter.py#L108) now runs on multislice environment to test larger models with utilities to compare maxtext and vllm weights.
+
+#### Deprecations
+
+- Legacy `MaxText.*` shims have been removed. Please refer to [src/MaxText/README.md](https://github.com/AI-Hypercomputer/maxtext/blob/0536605a8ca116087ed93178433a67e905be566c/src/MaxText/README.md) for details on the new command locations and how to migrate.
+- Sequence parallelism has been deprecated, please use context parallelism instead.
+- The flag `expert_shard_attention_option` is deprecated, use `custom_mesh_and_rule=ep-as-cp` for the same functionality.
+
 ### v0.2.1
 
+#### Changes
+
 - Use the new `maxtext[runner]` installation option to build Docker images without cloning the repository. This can be used for scheduling jobs through XPK. See the [MaxText installation instructions](https://maxtext.readthedocs.io/en/maxtext-v0.2.1/build_maxtext.html) for more info.
 - Config can now be inferred for most MaxText commands. If you choose not to provide a config, MaxText will now [select an appropriate one](https://github.com/AI-Hypercomputer/maxtext/blob/9e786c888cc7acdfc00a8f73064e285017e80b86/src/maxtext/configs/pyconfig.py#L51-L67).
 - Configs in MaxText PyPI will now be picked up without storing them locally.

src/maxtext/__init__.py

@@ -19,7 +19,7 @@
 """
 
 __author__ = "Google LLC"
-__version__ = "0.2.1"
+__version__ = "0.2.2"
 __description__ = (
     "MaxText is a high performance, highly scalable, open-source LLM written in pure Python/Jax and "
     "targeting Google Cloud TPUs and GPUs for training and **inference."