Remove UltraNest and PySwarms, clean up search tests

[Jammy2211]

Summary

Remove UltraNest and PySwarms search implementations from PyAutoFit to simplify the codebase and reduce dependencies. Both are archived in the new autofit_workspace_developer repo with runnable examples. Also adds Nautilus test coverage, expands abstract search tests, and fixes Nautilus copy-paste docstring bugs.

Closes #1190

API Changes

Three public symbols removed from the autofit namespace:

• af.UltraNest — use autofit_workspace_developer/searches/ultranest/ if needed
• af.PySwarmsGlobal — use autofit_workspace_developer/searches/pyswarms/ if needed
• af.PySwarmsLocal — use autofit_workspace_developer/searches/pyswarms/ if needed

One hard dependency removed: pyswarms==1.3.0 no longer required at install time.
One optional dependency removed: ultranest==4.3.2.

See full details below.

Test Plan

• All 1205 unit tests pass (pytest test_autofit/)
• python -c "import autofit as af" succeeds
• af.UltraNest, af.PySwarmsGlobal, af.PySwarmsLocal raise AttributeError
• grep -ri "ultranest\|pyswarms" autofit/ test_autofit/ returns zero matches
• Downstream workspace cleanup (separate follow-up)

Full API Changes (for automation & release notes)

Removed

• autofit.UltraNest — UltraNest nested sampling search class
• autofit.PySwarmsGlobal — PySwarms global-best particle swarm optimizer
• autofit.PySwarmsLocal — PySwarms local-best particle swarm optimizer
• pyswarms==1.3.0 from [project.dependencies]
• ultranest==4.3.2 from [project.optional-dependencies]
• Config blocks: UltraNest from nest.yaml, PySwarmsGlobal/PySwarmsLocal from mle.yaml

Added

• test_autofit/non_linear/search/nest/test_nautilus.py — 3 new Nautilus config tests
• 5 new tests in test_abstract_search.py — config dict access, unique_tag, path_prefix, identifier fields

Changed Behaviour

• autofit/non_linear/search/nest/nautilus/search.py — fixed docstrings that incorrectly referenced "ultranest"
• docs/features/interpolate.rst — fixed URL that pointed to UltraNest docs instead of Dynesty

Migration

• Before: search = af.UltraNest(min_num_live_points=400)
• After: Use Dynesty or Nautilus instead: search = af.DynestyStatic(nlive=400) or search = af.Nautilus(n_live=400)
• For advanced users who need UltraNest/PySwarms: install from autofit_workspace_developer repo

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main_build@655b629). Learn more about missing BASE report.

Additional details and impacted files

@@              Coverage Diff              @@
##             main_build    #1191   +/-   ##
=============================================
  Coverage              ?   80.23%           
=============================================
  Files                 ?      202           
  Lines                 ?    15787           
  Branches              ?        0           
=============================================
  Hits                  ?    12666           
  Misses                ?     3121           
  Partials              ?        0           

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Jammy2211]

Workspace PRs:

• Remove UltraNest and PySwarms references autofit_workspace#24
• Remove UltraNest and PySwarms config blocks autofit_workspace_test#2
• Remove UltraNest and PySwarms references autogalaxy_workspace#16
• Remove UltraNest and PySwarms config blocks autogalaxy_workspace_test#2
• Remove UltraNest and PySwarms references autolens_workspace#40
• Remove UltraNest and PySwarms config blocks autolens_workspace_test#15
• Remove UltraNest and PySwarms from no_run.yaml PyAutoBuild#38