Status page by source

[nrozanov]

Description

1. Split status by data source
2. Change staleness calculation for Forecaster / Scheduler sources (staleness should be calculated as difference between now and max event start time)

Look & Feel

1. "//status/" page should return source key as well
2. UI status page should include source

How to test

Is tested in test_sensor_data_schema.py (test_get_status_multi_source) Can be tested the following way - add data from several sources to some sensor. Go to its status page and check that statuses are split by this source column + scheduler/forecaster statuses are calculated differently

Further Improvements

Related Items

Follow up for https://github.com/FlexMeasures/flexmeasures/pull/941

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• [x] I agree to contribute to the project under Apache 2 License.
• [x] To the best of my knowledge, the proposed patch is not based on code under GPL or other license that is incompatible with FlexMeasures

[Flix6x]

@nrozanov if you edit this PR and set its base to 927-status-page, the diff should become a lot more to the point, making a review easier. (Once that base branch gets merged, and that branch will automatically get closed, this PR will get automatically rebased on main again.)

[nhoening]

Maybe that was based on my bad advice, forgot that the original branch is still open. I'm releasing now, so we can merge the other one in a bit.

[Flix6x]

I encountered the issue again where the status page falsely reports that no data is available from a forecaster data source type (see bottom right below). There is data from this forecaster for 22 June 2023.

Likewise for scheduler data source types (data is available for 18 June 2023):

Maybe we can take a look together tomorrow.