inverter class rewritten

[NormannK]

fully rewritten the inverter class
add tests

please check carefully
output from single_test_optimization.py is identical

[drbacke]

We should BE very carefull Here and a Lot of more Tests are required. The Inverter behaviour is very sensitive to Changes and Bugs are hard to find

[NormannK]

I increased the test coverage we do now test for:

1. Excess Generation: The system handles more generation than consumption, feeding excess to the grid and charging the battery.
2. Generation Equals Consumption: No feed-in or grid draw when generation matches consumption.
3. Battery Discharge: The battery discharges to help meet consumption, and the grid supplies any remaining shortfall.
4. Battery Empty: When the battery is empty, the grid covers the entire shortfall.
5. Battery Full at Start: When the battery is full, excess generation is fed into the grid.
6. Insufficient Generation, No Battery: When there’s insufficient generation and no battery discharge, the grid supplies the entire shortfall.
7. Insufficient Generation with Battery Assistance: The battery partially discharges to cover a shortfall, with the grid supplying the rest.
8. Zero Generation: When there’s zero generation, the system relies entirely on the battery and grid.
9. Zero Consumption: Verifies that when there is no consumption, the energy is either fed to the grid or used to charge the battery.
10. Zero Generation & Zero Consumption: Checks if the system correctly handles an idle state (no generation or consumption).
11. Partial Battery Discharge: Extends the test where the battery only partially covers the shortfall, with the grid providing the remaining energy.
12. Zero Generation, Full Battery, and High Consumption: Tests how well the inverter handles the case where only the battery and grid can fulfill consumption.

let me know if you have other scenarios we should test.

[NormannK]

There are some things that should be done too but would extend the logic and im not sure how other parts of the optimization would react.
I would not allow it to handle wrong values.
e.g. you can hand over a negative generation value. This cant handle and something should produce an error or do something. e,g, adding:

        if generation < 0:
            generation = 0.0  # Treat invalid negative generation as zero

[NormannK]

this should be the best test. i back ported the new test for the new class to the old class by only changing the import and the names of the function/variables called. minimal changes.
both files with _old should be deleted in a later PR if accepted.

[drbacke]

Please re-run all tests, code changed quite a lot

[NormannK]

done. only a single very easy conflict and the new test did need the new class

[NormannK]

redo tests

[NormannK]

@drbacke please review this PR. I did every safety check i can think of. Before merging both _old files should be removed.

[SREbuilt]

rename grid_feed_in --> grid_export and
rename grid_draw --> grid_import