Introduce a dummy azpysdk

[lmazuel]

Make the usage of uv easier and introduce a azpysdk CLI:

cd sdk/keyvault/azure-keyvault-keys

# uv approach
uv sync
uv run azpysdk --help

# venv approach
python3 -m venv .venv
source .venv/bin/activate
pip install -r dev_requirements.txt
azpysdk --help

This PR also move the azure-sdk-tools to pyproject.toml to simplify uv jobs with source dependencies.

Note: the uv approach requires to have imported the dev_requirements.txt in the pyproject.toml following PEP735 with

uv add -r dev_requirements.txt --group dev

[Copilot]

Pull Request Overview

This PR introduces a new azpysdk CLI tool to simplify development workflows and modernizes the azure-sdk-tools package configuration. The changes enable both uv and traditional venv approaches for managing Azure SDK Python development dependencies.

Key changes:

• Migrates azure-sdk-tools from setup.py to pyproject.toml for modern Python packaging
• Introduces a new azpysdk CLI with basic commands (greet, echo, run)
• Adds uv-compatible dependency management configuration to azure-keyvault-keys

Reviewed Changes

Copilot reviewed 4 out of 6 changed files in this pull request and generated 2 comments.

File	Description
sdk/keyvault/azure-keyvault-keys/pyproject.toml	Adds uv sources configuration and dev dependency group for improved dependency management
eng/tools/azure-sdk-tools/setup.py	Removes legacy setup.py configuration file
eng/tools/azure-sdk-tools/pyproject.toml	Migrates package configuration from setup.py to modern pyproject.toml format
eng/tools/azure-sdk-tools/azpysdk/main.py	Implements new azpysdk CLI with placeholder commands

[scbedd]

@microsoft-github-policy-service rerun

[scbedd]

/check-enforcer evaluate