chore: remove dead cookiecutter regeneration infrastructure

The repo was bootstrapped from `cookiecutter-pylibrary`. The
regeneration scaffolding has been sitting around since then — unused,
out of date, and in some cases pointing at infrastructure (AppVeyor)
that hasn't been part of CI for years. Knock it all down in one
sweep so there's nothing dead-by-design in the tree after this PR.

Removed
- `.cookiecutterrc` — cookiecutter regen metadata.
- `ci/bootstrap.py` — entry point for regenerating workflow files
  from the templates.
- `ci/templates/` (whole directory):
  - `.appveyor.yml` template (AppVeyor isn't wired up).
  - `.github/workflows/github-actions.yml` Jinja template (the live
    workflow has evolved past it via #32, #35, #37).

Coupled updates
- `tox.ini`: dropped the `[testenv:bootstrap]` env (calls deleted
  `bootstrap.py`) and the `bootstrap` reference in the basepython
  selector.
- `MANIFEST.in`: removed `include .cookiecutterrc`.
- `setup.cfg`: removed `ci/templates` from the flake8 `exclude` and
  isort `skip` lists (dead exclusion paths).
- `.pre-commit-config.yaml`: removed `ci/templates` from the
  top-level `exclude` regex.
- `tests.local.sh`: replaced the per-version `if/elif` chain (which
  still listed Python 3.7 and missed 3.12-3.14) with a single
  programmatic `tox -e py$VERSION` lookup against
  `tox --listenvs-all`. Self-maintaining when the matrix changes.
- `CHANGELOG.rst`: added a Housekeeping bullet for this PR.

Live and untouched
- `ci/requirements.txt` is still installed by every CI workflow
  (`pip install -r ci/requirements.txt`). Not regen-related.

Closes #46

3 files changed, 0 insertions, 204 deletions

diff --git a/ci/bootstrap.py b/ci/bootstrap.py
deleted file mode 100755
index 3ca06b7..0000000
--- a/ci/bootstrap.py
+++ /dev/null
@@ -1,93 +0,0 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
-from __future__ import absolute_import
-from __future__ import print_function
-from __future__ import unicode_literals
-
-import os
-import subprocess
-import sys
-from os.path import abspath
-from os.path import dirname
-from os.path import exists
-from os.path import join
-from os.path import relpath
-
-base_path = dirname(dirname(abspath(__file__)))
-templates_path = join(base_path, "ci", "templates")
-
-
-def check_call(args):
-    print("+", *args)
-    subprocess.check_call(args)
-
-
-def exec_in_env():
-    env_path = join(base_path, ".tox", "bootstrap")
-    if sys.platform == "win32":
-        bin_path = join(env_path, "Scripts")
-    else:
-        bin_path = join(env_path, "bin")
-    if not exists(env_path):
-        import subprocess
-
-        print("Making bootstrap env in: {0} ...".format(env_path))
-        try:
-            check_call([sys.executable, "-m", "venv", env_path])
-        except subprocess.CalledProcessError:
-            try:
-                check_call([sys.executable, "-m", "virtualenv", env_path])
-            except subprocess.CalledProcessError:
-                check_call(["virtualenv", env_path])
-        print("Installing `jinja2` into bootstrap environment...")
-        check_call([join(bin_path, "pip"), "install", "jinja2", "tox"])
-    python_executable = join(bin_path, "python")
-    if not os.path.exists(python_executable):
-        python_executable += '.exe'
-
-    print("Re-executing with: {0}".format(python_executable))
-    print("+ exec", python_executable, __file__, "--no-env")
-    os.execv(python_executable, [python_executable, __file__, "--no-env"])
-
-
-def main():
-    import jinja2
-
-    print("Project path: {0}".format(base_path))
-
-    jinja = jinja2.Environment(
-        loader=jinja2.FileSystemLoader(templates_path),
-        trim_blocks=True,
-        lstrip_blocks=True,
-        keep_trailing_newline=True,
-    )
-
-    tox_environments = [
-        line.strip()
-        # 'tox' need not be installed globally, but must be importable
-        # by the Python that is running this script.
-        # This uses sys.executable the same way that the call in
-        # cookiecutter-pylibrary/hooks/post_gen_project.py
-        # invokes this bootstrap.py itself.
-        for line in subprocess.check_output([sys.executable, '-m', 'tox', '--listenvs'], universal_newlines=True).splitlines()
-    ]
-    tox_environments = [line for line in tox_environments if line.startswith('py')]
-
-    for root, _, files in os.walk(templates_path):
-        for name in files:
-            relative = relpath(root, templates_path)
-            with open(join(base_path, relative, name), "w") as fh:
-                fh.write(jinja.get_template(join(relative, name)).render(tox_environments=tox_environments))
-            print("Wrote {}".format(name))
-    print("DONE.")
-
-
-if __name__ == "__main__":
-    args = sys.argv[1:]
-    if args == ["--no-env"]:
-        main()
-    elif not args:
-        exec_in_env()
-    else:
-        print("Unexpected arguments {0}".format(args), file=sys.stderr)
-        sys.exit(1)
diff --git a/ci/templates/.appveyor.yml b/ci/templates/.appveyor.yml
deleted file mode 100644
index 956e594..0000000
--- a/ci/templates/.appveyor.yml
+++ /dev/null
@@ -1,46 +0,0 @@
-version: '{branch}-{build}'
-build: off
-image: Visual Studio 2019
-environment:
-  matrix:
-    - TOXENV: check
-      TOXPYTHON: C:\Python38\python.exe
-      PYTHON_HOME: C:\Python38
-      PYTHON_VERSION: '3.8'
-      PYTHON_ARCH: '32'
-{% for env in tox_environments %}
-{% if env.startswith(('py2', 'py3')) %}
-    - TOXENV: {{ env }},codecov{{ "" }}
-      TOXPYTHON: C:\Python{{ env[2:4] }}\python.exe
-      PYTHON_HOME: C:\Python{{ env[2:4] }}
-      PYTHON_VERSION: '{{ env[2] }}.{{ env[3] }}'
-      PYTHON_ARCH: '32'
-{% if 'nocov' in env %}
-      WHEEL_PATH: .tox/dist
-{% endif %}
-    - TOXENV: {{ env }},codecov{{ "" }}
-      TOXPYTHON: C:\Python{{ env[2:4] }}-x64\python.exe
-      PYTHON_HOME: C:\Python{{ env[2:4] }}-x64
-      PYTHON_VERSION: '{{ env[2] }}.{{ env[3] }}'
-      PYTHON_ARCH: '64'
-{% if 'nocov' in env %}
-      WHEEL_PATH: .tox/dist
-{% endif %}
-{% endif %}{% endfor %}
-init:
-  - ps: echo $env:TOXENV
-  - ps: ls C:\Python*
-install:
-  - '%PYTHON_HOME%\python -mpip install --progress-bar=off tox -rci/requirements.txt'
-  - '%PYTHON_HOME%\Scripts\virtualenv --version'
-  - '%PYTHON_HOME%\Scripts\pip --version'
-  - '%PYTHON_HOME%\Scripts\tox --version'
-test_script:
-  - %PYTHON_HOME%\Scripts\tox
-on_failure:
-  - ps: dir "env:"
-  - ps: get-content .tox\*\log\*
-
-### To enable remote debugging uncomment this (also, see: http://www.appveyor.com/docs/how-to/rdp-to-build-worker):
-# on_finish:
-#   - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))
diff --git a/ci/templates/.github/workflows/github-actions.yml b/ci/templates/.github/workflows/github-actions.yml
deleted file mode 100644
index eb42d88..0000000
--- a/ci/templates/.github/workflows/github-actions.yml
+++ /dev/null
@@ -1,65 +0,0 @@
-name: build
-on: [push, pull_request]
-jobs:
-  test:
-    name: {{ '${{ matrix.name }}' }}
-    runs-on: {{ '${{ matrix.os }}' }}
-    timeout-minutes: 30
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - name: 'check'
-            python: '3.9'
-            toxpython: 'python3.9'
-            tox_env: 'check'
-            os: 'ubuntu-latest'
-          - name: 'docs'
-            python: '3.9'
-            toxpython: 'python3.9'
-            tox_env: 'docs'
-            os: 'ubuntu-latest'
-{% for env in tox_environments %}
-{% set prefix = env.split('-')[0] -%}
-{% if prefix.startswith('pypy') %}
-{% set python %}pypy-{{ prefix[4] }}.{{ prefix[5] }}{% endset %}
-{% set cpython %}pp{{ prefix[4:5] }}{% endset %}
-{% set toxpython %}pypy{{ prefix[4] }}.{{ prefix[5] }}{% endset %}
-{% else %}
-{% set python %}{{ prefix[2] }}.{{ prefix[3:] }}{% endset %}
-{% set cpython %}cp{{ prefix[2:] }}{% endset %}
-{% set toxpython %}python{{ prefix[2] }}.{{ prefix[3:] }}{% endset %}
-{% endif %}
-{% for os, python_arch in [
-    ['ubuntu', 'x64'],
-    ['windows', 'x64'],
-    ['macos', ''],
-] %}
-          - name: '{{ env }} ({{ os }})'
-            python: '{{ python }}'
-            toxpython: '{{ toxpython }}'
-            {% if python_arch %}python_arch: '{{ python_arch }}'
-            {% endif %}tox_env: '{{ env }}{% if 'cover' in env %},codecov{% endif %}'
-            os: '{{ os }}-latest'
-{% endfor %}
-{% endfor %}
-    steps:
-    - uses: actions/checkout@v2
-      with:
-        fetch-depth: 0
-    - uses: actions/setup-python@v2
-      with:
-        python-version: {{ '${{ matrix.python }}' }}
-        architecture: {{ '${{ matrix.python_arch }}' }}
-    - name: install dependencies
-      run: |
-        python -mpip install --progress-bar=off -r ci/requirements.txt
-        virtualenv --version
-        pip --version
-        tox --version
-        pip list --format=freeze
-    - name: test
-      env:
-        TOXPYTHON: '{{ '${{ matrix.toxpython }}' }}'
-      run: >
-        tox -e {{ '${{ matrix.tox_env }}' }} -v