0.7.5

## What's Changed
- [feat: add endpoints for counts of agents, identities, sources, & tools](https://github.com/letta-ai/letta/pull/2587/commits/d21ab7877728fb48c6d727b1b1e94cb1eb1c6169)
- [fix: sleeptime agent deletion race](https://github.com/letta-ai/letta/pull/2587/commits/5863c448d5de4ed8dbb679ffdd8e78dc8d910fe7)
- [fix: azure context window limits for new models](https://github.com/letta-ai/letta/pull/2587/commits/4f993b2b92f2df0423cbb9caa6c87ac63c016a67)