add API layout strategy

[thomas-maschler]

Related Issue(s):

• Support to write to STAC APIs pystac-client#241

Description:
This PR implements the API Layout Strategy following the STAC API Specifications.
Unlike the Best Practice Layout Strategy, this strategy is not based on file paths. Instead, it uses HTTP endpoints. This requires refactoring of Catalog's add_child, add_item, and update_href methods not to remove the last path element. Instead, I moved this step into the HrefLayoutStrategy.get_href method and made it conditional based on whether the path is a file or not.

Together with #1295, this PR is part of setting the foundation for enabling API transactions using pystac-client.

PR Checklist:

• pre-commit hooks pass locally
• Tests pass (run scripts/test)
• Documentation has been updated to reflect changes, if applicable
• This PR maintains or improves overall codebase code coverage.
• Changes are added to the CHANGELOG. See the docs for information about adding to the changelog.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (0407be2) 91.12% compared to head (0c372e0) 91.17%.
Report is 1 commits behind head on main.

❗ Current head 0c372e0 differs from pull request most recent head 199211c. Consider uploading reports for the commit 199211c to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1294      +/-   ##
==========================================
+ Coverage   91.12%   91.17%   +0.05%     
==========================================
  Files          51       51              
  Lines        6994     7015      +21     
  Branches     1001     1004       +3     
==========================================
+ Hits         6373     6396      +23     
+ Misses        444      443       -1     
+ Partials      177      176       -1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[jsignell]

Sorry for the slow response. This looks really good to me. I was kind of surprised that this didn't exist yet in pystac.

[thomas-maschler]

Thanks for the review. I added a docstring

[thomas-maschler]

@jsignell I had to resolve a conflict in the change log. Can you resubmit?