HNDS-R: support post geojson to dataset page

[alee]

What's Changed

• feat: allow geojson POSTs to select area page by @alee in feat: allow geojson POSTs to select area page #197 - this allows other websites to POST geojson to the select area page for a given dataset and have the geojson loaded in automagically. related issue
• add server side error messages back to timeseries plots to indicate timeouts, etc.

Full Changelog: v2023.01...v2023.07

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This discussion was created from the release HNDS-R: support post geojson to dataset page.