0.10.0

This release introduces a new `LettaPing` message type for maintaining long streaming connections, MCP OAuth support, and various bugfixes and performance improvements. 

## 🏓 `LettaPing` message type for long-running streaming requests 
To avoid connection terminations during long running tools, Letta will send a `LettaPing` message at a specific interval - currently 90 seconds ([#3651](https://github.com/letta-ai/letta/commit/215cdeaa0b332a2569a1b66c9d0a78970be79b78), [#3652](https://github.com/letta-ai/letta/commit/30cacc3cdb17e90154652eeac1c864aacf2281ad), [#3647](https://github.com/letta-ai/letta/commit/1b43f1ed6630d6cfa947fce4722e9ae4a1c15e63)). You will only see the `LettaPing` message if your tool execution takes longer than the ping interval, and you are using streaming endpoints. 

_⚠️ Warning: If you have long running tools, you may need to add handling for for this new message type in your applications. In future releases, the ping interval will be reduced to 50 seconds. ⚠️_

## Moving to `memgpt_v2_agent` base architecture ([#3624](https://github.com/letta-ai/letta/commit/2a2facd4f98b1e433222b0104bd33d46252f9b7f))
**Default Agent Architecture Change**: Letta now defaults to the new `memgpt_v2_agent` architecture (see [documentation](https://docs.letta.com/guides/agents/architectures/memgpt#memgpt-v2-the-latest-iteration-of-memgpt)). Archival memory tools are also no longer added by default, but can be added explicitly. 

## 🔐 MCP OAuth Support 
We now support OAuth MCP providers such as Linear and Github. 

## 🧠 LLM Provider Patches
We've added patches and improved support for LMStudio and Ollama: 
- **LMStudio**: Added support for Qwen and Llama models with manual token counting for streaming
- **Ollama**: integration moved to new agent loop architecture ([#3615](https://github.com/letta-ai/letta/commit/977d5d8e0ccad285e91983b2c629f93986293138))

## Bug Fixes

- Fixed null check in voice endpoint ([#3690](https://github.com/letta-ai/letta/commit/fede832988730acc47439d2e0176acadcfbb1325))
- Fixed builtin web search tests ([#3680](https://github.com/letta-ai/letta/commit/7594e39238ae4b5772bf01202520d8ca0591057d))
- Fixed flaky test issues ([#3629](https://github.com/letta-ai/letta/commit/11ebcd8801ade1ef73c8adde54922afeaf8cfb84))

## Other Improvements

- Removed deprecation warnings and excessive logging ([#3560](https://github.com/letta-ai/letta/commit/6977dfd882f3a7c6d5b67693a806c12f929d74e9))
- Updated test infrastructure to use Gemini 2.5 ([#3548](https://github.com/letta-ai/letta/commit/e8eda8fe72bfc7b84aef4701adc8460aee743e77))
- Set default Letta environment to dev for OSS ([#3627](https://github.com/letta-ai/letta/commit/8ae2153f06a46066c3deec08bf82beeb0f92fd13))
- Added modal sandbox functionality with conditional imports ([commit](https://github.com/letta-ai/letta/commit/bfc633f166fa84d0029d83e31c9ee881eafbb15b), [#3668](https://github.com/letta-ai/letta/commit/08825ef523923d4c0edf59d2f39d925dcd36816c))
- Added `not_indexable` property to agents ([#3653](https://github.com/letta-ai/letta/commit/96ddc0a0ac7135266f438162035b773073244585))
- Improved name generation ([#3592](https://github.com/letta-ai/letta/commit/3ec86735accdf937e6dc78d7eedc0fe8e0a9211e))
- Default project configuration for agent listings ([#3660](https://github.com/letta-ai/letta/commit/5b580e66ed6d5fe6be20bf8d088ef0cf7b1bcb3e))
- Removed OpenTelemetry file exports ([#3691](https://github.com/letta-ai/letta/commit/ae617fe59ca96b54cfd751839bb905a3daec0592))
- API key validation before using token counter for Anthropic ([#3628](https://github.com/letta-ai/letta/commit/7c06e222042378b74983669444dfc416a43d5390))
- Async system prompt compilation for better performance ([#3685](https://github.com/letta-ai/letta/commit/35bef8fa968a7ad7de30378695d320e50ecc0ca4))
- Memory blocks viewer for better memory management ([#3610](https://github.com/letta-ai/letta/commit/af0fc8d96181fcb06136f17d34edbe12bc41bafa))
- Polished open files tools ([#3575](https://github.com/letta-ai/letta/commit/3a70d6c75a198464bbeb46e57253ca9e702979f5))
- Desktop application improvements ([#3537](https://github.com/letta-ai/letta/commit/a164df365dab5ed421f634ed5f76d18aeebcdece))
- Web search performance optimizations ([#3650](https://github.com/letta-ai/letta/commit/b5fd7a0a5e497f8ad6cf0b7750131c09bf52e6eb), [#3649](https://github.com/letta-ai/letta/commit/75ce77b74111a0ac2cf2a68406f9b9d6049c4759))
- Enhanced error handling for cancellations ([#3641](https://github.com/letta-ai/letta/commit/bbe71e4ecba4057a2f32c2ca4045f01fbc0db1a0))
- Enhanced tool generation with better prompting ([#3633](https://github.com/letta-ai/letta/commit/5c59185cc103eae191d43af693d33360c02f23e9), [#3635](https://github.com/letta-ai/letta/commit/536a3058620eb72495f5bb353305fa8ebaf1091f))
- Improved tool renaming based on JSON schema ([#3676](https://github.com/letta-ai/letta/commit/ad8cab11a9b20865633a3b3bbe1aab32e3d9bace))
- Multi-function files support with documentation ([#3679](https://github.com/letta-ai/letta/commit/4f1c1ab503c7819c82d538be24f5212bc84334ab))