Add devcontainer, fix breaking change in azure-ai-projects, add dependabot

[iMicknl]

Purpose

This pull request introduces several key changes to the development environment and the enterprise-streaming-agent.ipynb notebook. The most important changes include the addition of a dev container configuration, setting up Dependabot for automated dependency updates, and updating the notebook with execution counts and outputs.

Development Environment Enhancements:

• Added a new dev container configuration file .devcontainer/devcontainer.json to streamline the development setup with Python 3, Azure CLI, and UV features. The container also forwards port 7861 and installs required Python packages upon creation.

• Configured Dependabot in .github/dependabot.yml to automate dependency updates for devcontainers and pip packages on a weekly schedule.

Notebook Updates:

• Updated enterprise-streaming-agent.ipynb with execution counts and outputs for various cells to reflect actual execution results, including outputs for connection and file upload status, tool execution, agent creation, and thread creation. [1] [2] [3] [4] [5] [6] [7]

• Corrected a parameter name in the notebook from assistant_id to agent_id to ensure proper agent streaming functionality.

• Updated the notebook metadata to reflect the correct Python version and display name. [1] [2]

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[x] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe: