Fix tox configuration for direct usage without uv

- Removed `runner = uv-venv-runner` from all tox environments to ensure compatibility with direct tox usage
- Changed from `uv pip install` to standard `pip install` commands in tox environments
- Removed tox-uv dependency from pyproject.toml and GitHub Actions workflow
- Fixed integration test environment pytest configuration conflict

This resolves the KeyError: 'uv-venv-runner' issue when running `tox -e <env>` directly
instead of `uv run tox -e <env>`. Now tox works consistently across all environments.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ritwik-g

.github/workflows/ci.yml

@@ -36,7 +36,7 @@ jobs:
 
     - name: Install tox
       run: |
-        pip install tox tox-uv
+        pip install tox
 
     - name: Run tests with tox
       run: |

pyproject.toml

@@ -26,7 +26,6 @@ dev-dependencies = [
     "ruff>=0.1.0",
     "mypy>=1.0.0",
     "tox>=4.0.0",
-    "tox-uv>=1.0.0",
 ]
 
 [tool.ruff]

tox.ini

@@ -3,15 +3,13 @@ envlist = py39,py310,py311,py312,lint,type-check
 isolated_build = true
 
 [testenv]
-# Use uv for package management
-runner = uv-venv-runner
-# Install dependencies via uv
+# Install dependencies via standard tox, use uv for editable install
 deps = 
     pytest>=7.0
     pytest-cov>=4.0
-# Install the package itself in editable mode with uv
+# Install the package itself in editable mode
 commands_pre =
-    uv pip install -e .
+    pip install -e .
 commands = 
     pytest tests/ -v --cov=helm_values_manager --cov-report=xml --cov-report=term
 setenv =
@@ -33,32 +31,29 @@ basepython = python3.11
 basepython = python3.12
 
 [testenv:lint]
-runner = uv-venv-runner
 deps =
     ruff>=0.1.0
 commands =
     ruff check .
     ruff format --check .
 
 [testenv:type-check]
-runner = uv-venv-runner
 deps =
     mypy>=1.0
     types-PyYAML
     types-setuptools
 commands_pre =
-    uv pip install -e .
+    pip install -e .
 commands =
     mypy helm_values_manager --ignore-missing-imports
 
 [testenv:integration]
-runner = uv-venv-runner
 deps = 
     pytest>=7.0
 commands_pre =
-    uv pip install -e .
+    pip install -e .
 commands =
-    pytest tests/test_integration.py -v
+    pytest tests/test_integration.py -v --override-ini="addopts="
 setenv =
     FORCE_COLOR = 0
     NO_COLOR = 1