fix(test): set pip install path in docker container

Changes:
- Add HOME and PYTHONUSERBASE environment variables to docker container
- Fix permission issues when pip tries to install packages as non-root user
- Add .cache/ and .local-build/ to .gitignore

This resolves the "Permission denied: '/.local'" error when running
pip install --user inside the container with --user flag.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: SckyzO

.gitignore

@@ -37,6 +37,8 @@ archives/
 tmp/
 site/
 *.egg-info/
+.cache/
+.local-build/
 
 # --- Secrets & Environment Variables ---
 secrets/

core/scripts/local_test.sh

@@ -147,6 +147,8 @@ generate_build_files() {
             --user $(id -u):$(id -g) \
             -v \"$PROJECT_ROOT:/workspace:rw\" \
             -w /workspace \
+            -e HOME=/workspace \
+            -e PYTHONUSERBASE=/workspace/.local-build \
             python:3.11-slim \
             bash -c \"
                 pip install -q --user -r requirements/base.txt && \