Add pyproject.toml packaging and optional event properties - #2

What

This PR adds two independent enhancements to the mida-python SDK:

1. Optional event properties: Added properties parameter to set_event() to support event metadata (e.g., revenue tracking)
2. Modern Python packaging: Added pyproject.toml for standards-compliant packaging and distribution

Why

Event Properties: Server-side SDKs should support event properties for tracking additional context like revenue, quantity, product IDs, etc. This matches the capabilities of the Node.js and PHP SDKs.

Packaging: The repository had no packaging configuration, requiring users to manually copy mida.py and install dependencies. A proper pyproject.toml enables:

• pip install . from the repository
• Future PyPI distribution with pip install mida-python
• Proper dependency management
• Standard Python packaging workflows

Changes

Event Properties

• set_event(event_name, distinct_id, properties=None) now accepts an optional properties dict
• When provided, properties are serialized to JSON and sent as a properties field (matching Node.js/PHP SDK wire format)
• Fully backwards compatible (old code without properties continues to work)
• Added test in tests/test_set_event.py that verifies both with and without properties

Packaging

• Added pyproject.toml with:
  • setuptools>=61 build backend
  • Package name: mida-python (placeholder, see notes below)
  • Version: 0.1.0 (placeholder, see notes below)
  • requests dependency declared
  • Proper metadata (description, license, URLs, keywords)
  • py-modules = ["mida"] to package the single-file module
• Updated README install instructions to show pip install . workflow
• Added .gitignore for Python build artifacts
• Successfully builds both wheel and source distributions

Risk

Low risk - Both changes are backwards compatible:

• Code not using properties parameter continues to work unchanged
• The packaging doesn't change how the module is used (just how it's installed)

Merge Conflicts

⚠️ Expected conflicts with PR #1 (feature flag cache fix):

• README.md: Both PRs modify the "Methods" section and the usage example. This PR updates installation instructions and set_event documentation while PR Fix feature flag cache to be keyed per user #1 updates is_feature_enabled documentation. Manual merge will combine both changes.
• .gitignore: Both PRs add identical .gitignore files (no actual conflict, just duplicate adds)

These conflicts are expected and resolvable. The patches are functionally independent.

Important Notes

🚨 Placeholders for Donald to confirm before publishing:

1. Package name: Currently set to mida-python in pyproject.toml

   • PyPI availability was not checked
   • May need to be changed if the name is taken or if a different name is preferred

2. Version: Currently set to 0.1.0

   • Should be confirmed or adjusted based on versioning strategy

3. License format warning: The build shows a deprecation warning about license = { text = "MIT" }

   • Consider updating to license = "MIT" (requires setuptools>=77.0.0 or later)
   • Current format works but will be unsupported by 2027-Feb-18

How to Verify

Test event properties:

python3 tests/test_set_event.py

Tests verify:

• Events without properties send the original payload
• Events with properties include a JSON-stringified properties field

Build the package:

pip install build
python3 -m build

Should successfully create:

• dist/mida_python-0.1.0.tar.gz (source distribution)
• dist/mida_python-0.1.0-py3-none-any.whl (wheel)

Install and test locally:

pip install dist/mida_python-0.1.0-py3-none-any.whl
python3 -c "from mida import Mida; m = Mida('test'); print('Import works!')"