60: add form creation

[lindsay-stevens]

Closes #60

Adds method client.forms.create. There is a parameter for ignore_warnings which defaults to False. The publish parameter is hard coded to True as per #60. The form ID logic is slightly different, as follows - since pyODK has a form_id param and potentially a file path it seemed sensible to prioritise those before a uuid-based form ID fallback.

form_id defaults behaviour for create/update:

• was:
  • form_id in the file (assuming Central reads and prioritises that)
  • definition file_path.stem
• now:
  • form_id in the file (assuming Central reads and prioritises that)
  • form_id (or default) provided to pyodk
  • definition file_path.stem
  • random UUID

Also since I anticipated this being used in pyxform-http or similar I made create/update accept bytes. So you could read in the request and send it off without writing to a file. I didn't add that for attachments but it could be done as well. I also had in mind Sam from HOT's recent request for pyxform to support passing in bytes in addition to paths.

What has been done to verify that this works as intended?

Unit tests and E2E tests. Manually verified valid forms were uploaded.

Why is this the best possible solution? Were any other approaches considered?

If the bytes thing seems too much, it's pretty much contained to 36fe156 so that could be dropped if preferred.

How does this change affect users? Describe intentional changes to behavior and behavior that could have accidentally been affected by code changes. In other words, what are the regression risks?

New method to create forms. For update, the definition kwarg now accepts PathLike or bytes in addition to a string path.

Do we need any specific form for testing your changes? If so, please attach one.

No, this PR pulls in xlwt as a dependency for XLS files so we can steadfastly not add binary test fixtures. On the XLS topic, I vendorised (but credited in comments) an external XLS detection function.

Does this change require updates to documentation? If so, please file an issue here and include the link below.

The auto-generated docs would show the new methods.

Before submitting this PR, please make sure you have:

• included test cases for core behavior and edge cases in tests
• run python -m unittest and verified all tests pass
• run ruff format pyxform tests and ruff check pyxform tests to lint code
• verified that any code or assets from external sources are properly credited in comments

[lognaturel]

Looks great! Nice additions. 👍

We didn't have this in the original issue but I'm realizing it'd be nice to be able to specify attachments in the same way as with an update. Right now to add attachments you'd have to first create and then update which is fine but would be great to avoid. That can be in a follow-up PR or in this one, @lindsay-stevens