Switch to src layout, move tests to root

[effigies]

Closes #147.

Also, somehow, closes #131. See #131 (comment).

$ du -sh dist/*  12K	dist/lazy_loader-0.5rc0.dev0-py3-none-any.whl 16K	dist/lazy_loader-0.5rc0.dev0.tar.gz $ tar -tf dist/*.tar.gz lazy_loader-0.5rc0.dev0/ lazy_loader-0.5rc0.dev0/CHANGELOG.md lazy_loader-0.5rc0.dev0/LICENSE.md lazy_loader-0.5rc0.dev0/MANIFEST.in lazy_loader-0.5rc0.dev0/PKG-INFO lazy_loader-0.5rc0.dev0/README.md lazy_loader-0.5rc0.dev0/pyproject.toml lazy_loader-0.5rc0.dev0/setup.cfg lazy_loader-0.5rc0.dev0/src/ lazy_loader-0.5rc0.dev0/src/lazy_loader/ lazy_loader-0.5rc0.dev0/src/lazy_loader/__init__.py lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/ lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/PKG-INFO lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/SOURCES.txt lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/dependency_links.txt lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/requires.txt lazy_loader-0.5rc0.dev0/src/lazy_loader.egg-info/top_level.txt lazy_loader-0.5rc0.dev0/tests/ lazy_loader-0.5rc0.dev0/tests/__init__.py lazy_loader-0.5rc0.dev0/tests/fake_pkg/ lazy_loader-0.5rc0.dev0/tests/fake_pkg/__init__.py lazy_loader-0.5rc0.dev0/tests/fake_pkg/__init__.pyi lazy_loader-0.5rc0.dev0/tests/fake_pkg/some_func.py lazy_loader-0.5rc0.dev0/tests/import_np_parallel.py lazy_loader-0.5rc0.dev0/tests/test_lazy_loader.py $ unzip -l dist/*.whl Archive: dist/lazy_loader-0.5rc0.dev0-py3-none-any.whl  Length Date Time Name --------- ---------- ----- ----  10909 05-17-2025 13:57 lazy_loader/__init__.py  1539 05-17-2025 13:57 lazy_loader-0.5rc0.dev0.dist-info/licenses/LICENSE.md  7515 05-17-2025 13:57 lazy_loader-0.5rc0.dev0.dist-info/METADATA  91 05-17-2025 13:57 lazy_loader-0.5rc0.dev0.dist-info/WHEEL  12 05-17-2025 13:57 lazy_loader-0.5rc0.dev0.dist-info/top_level.txt  529 05-17-2025 13:57 lazy_loader-0.5rc0.dev0.dist-info/RECORD --------- -------  20595 6 files

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.27%. Comparing base (024e49f) to head (79aa9d0).
Report is 1 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@ ## main #151 +/- ## ========================================== - Coverage 96.00% 87.27% -8.73%  ========================================== Files 5 1 -4 Lines 250 110 -140 Branches 0 20 +20 ========================================== - Hits 240 96 -144  + Misses 10 7 -3  - Partials 0 7 +7 

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[stefanv]

Thanks, @effigies! src layout isn't common in the SP ecosystem, but I don't feel strongly about it. Not sure I follow why this closes #131 🤷‍♂️