Url based remote dataset import

[knollengewaechs]

URL of deployed dev instance (used for testing):

• https://urlbasedremotedatasetimport.webknossos.xyz/

Steps to test:

• pick any remote dataset, and use route /import?url=<...>. Ideally the dataset should open after a bit of loading
• make sure the usual remote DS upload is still working
• try causing an error during upload (no/wrong URL, use dataset twice etc) and check that you are seeing the upload form wirh an appropriate error
• if you open a dataset that has been imported before, you should directly be redirected to the dataset view

TODOs:

• fix modal The explored data has a different voxel size from the datasource that was already loaded.
• add animation in order not to show form in happy path
• infer name and automatically submit second form in happy path
• right now its hard to load the real errors in handleStoreDataset (form.validateFields()). maybe theres a good way to print only the relevant fields?
• route to login if needed
  • route to form afterwards: only keep URI parameter
• code self-review and clean-up.
  • prevent mutliple isNameValid calls! handleStoreDataset seems to only be called once...
• TEST!!!
• fix theme of PW field in add layer modal
• append url hash to name
• if url has been imported before, open existing DS
• fix that brain spinner is jumping when loading DS (edit: skipped for now. I think this happens if the navbar changes from text to icons, I didnt find an easy reason and it doesnt seem worth to spend more time there
• change label if url is edited

Issues:

• fixes URL-based remote dataset import #7686

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(Please delete unneeded items, merge only when none are left open)

• Updated changelog
• Updated migration guide if applicable
• Updated documentation if applicable
• Adapted wk-libs python client if relevant API parts change
• Removed dev-only changes like prints and application.conf edits
• Considered common edge cases
• Needs datastore update after deployment

[knollengewaechs]

this was failing in my case because the dataSourceJson didnt contain the scale at some point. It seems to me that its still making sense, but I just want to make sure that its not problematic in another case.

• obvs check whether usual remote DS upload is still working fine

[philippotto]

looking good overall! left a couple of comments :)

[philippotto]

great! I didn't do a final test, since I assume you will do (or have done) this before the merge :)

[knollengewaechs]

Amazing, thank you! Yes, I tested it just now and it still seems to be working good. I will quickly test it again tomorrow right before merging.
Sorry if I am being nit-picky, but do you think the other thread in this commit is resolved? Just trying to make sure I didnt miss anything.