fix: ci poetry installs into system python

poetry.toml sets virtualenvs.create=false, so pipx poetry installed into
the runner's system Python 3.12 and failed uninstalling Debian packages.
Force venv creation in CI via POETRY_VIRTUALENVS_CREATE. Drop the poetry
cache from release, which never creates a venv.

.github/workflows/pre-commit.yml

@@ -2,6 +2,7 @@ name: Pre-Commit Checks
 
 env:
   POETRY_VERSION: "2.4.1"
+  POETRY_VIRTUALENVS_CREATE: "true"
 
 
 on:

.github/workflows/release.yml

@@ -24,7 +24,6 @@ jobs:
         uses: actions/setup-python@v4
         with:
           python-version: "3.14"
-          cache: "poetry"
       - name: Build project for distribution
         run: poetry build --format sdist
       - name: Check Version

.github/workflows/test.yml

@@ -8,6 +8,7 @@ on:
 
 env:
   POETRY_VERSION: "2.4.1"
+  POETRY_VIRTUALENVS_CREATE: "true"
   OPENAI_API_KEY: "sk-fake"
 
 jobs: