tests: add inverter factory coverage

[filiplajszczak]

This adds coverage for common inverter factory behavior around MQTT creation, max_charge_rate alias handling, unknown type rejection, and Fronius config/default mapping. Backend-specific behavior stays in backend-specific test files.

It also switches pytest import-path handling to pythonpath = src, so the new test file does not need manual sys.path setup.

@MaStr One tooling question in the same spirit: would you be open to using uv in CI/setup instead of pip? I noticed the project is currently pinned to an older uv line in pyproject.toml, so I’m also wondering whether you’d be open to upgrading that pin first, if needed.

[MaStr]

Thank you for that.

About the question about switching from pip to uv: 100% yes, but under a different PR please.

I tried this a couple of weeks ago and ran in multiple issues (local setup, workflows, Dockerimage and HA repository). If you like to give it a try, I would love to take that one.
After the release of 3.14 (which is another bigger task), I ran into some pip/python issues on my arch system, which would had been solved by having an uv environment.

[Copilot]

Pull request overview

Adds new pytest coverage for the inverter factory to validate common configuration behavior and inverter instantiation, and updates pytest configuration to simplify imports from src/.

Changes:

• Added tests/batcontrol/inverter/test_inverter_factory.py covering MQTT creation, max_charge_rate aliasing, unknown-type rejection, and Fronius config/default mapping.
• Updated pytest.ini to add pythonpath = src for cleaner import-path handling.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
tests/batcontrol/inverter/test_inverter_factory.py	New tests validating factory behavior for MQTT and Fronius inverters and error handling.
pytest.ini	Adds src to pytest’s import path to avoid per-test sys.path setup.