fix(packaging): prevent unwanted files and tests from being installed

Refine package discovery and manifest exclusions to clean up both
wheels and source distributions (sdists):

- Dev-only paths like `tools/` and `example/` are not installed in
wheels.
- The `codespell_lib.tests` subpackage is excluded from the wheel.
- Only files explicitly listed in `package-data` are bundled in wheels.
- Dev metadata (.github, .devcontainer, .gitignore, .mailmap) is pruned
from sdists.

Signed-off-by: Mikel Olasagasti Uranga <mikel@olasagasti.info>

Author: mikelolasagasti

MANIFEST.in

@@ -2,6 +2,10 @@ exclude *.yml *.yaml
 exclude .coveragerc
 exclude .git-blame-ignore-revs
 exclude example example/* snap snap/*
+prune .devcontainer
+prune .github
+exclude .gitignore
+exclude .mailmap
 exclude Makefile
 exclude codespell.1.include
 exclude pyproject-codespell.precommit-toml

pyproject.toml

@@ -70,10 +70,17 @@ requires = ["setuptools>=77", "setuptools_scm[toml]>=6.2, != 8.0.0"]
 [tool.setuptools_scm]
 write_to = "codespell_lib/_version.py"
 
+[tool.setuptools]
+include-package-data = false
+
 [tool.setuptools.packages.find]
+include = ["codespell_lib", "codespell_lib.*"]
 exclude = [
     "dist",
     "snap",
+    "tools",
+    "example",
+    "codespell_lib.tests*",
 ]
 
 [tool.setuptools.package-data]