Replace the previous `pip install calibreweb` and `uv sync` steps with explicit upgrades of pip/setuptools/wheel and installing dependencies from requirements.txt. If present, optional-requirements.txt is installed as well. Changes applied to both the installer and container update scripts to provide clearer, reproducible dependency management.
Remove the conditional retry logic and always run the venv creation, pip install of calibreweb, and uv sync without build isolation. Updated ct/calibre-web.sh and install/calibre-web-install.sh to: run `$STD uv venv`, `$STD uv pip install --python /opt/calibre-web/.venv/bin/python --no-cache-dir calibreweb`, then `$STD uv sync --no-dev --no-build-isolation`. This simplifies the dependency installation flow and ensures the virtualenv and package are installed before syncing.
Add retry logic to ct/calibre-web.sh and install/calibre-web-install.sh: if 'uv sync --no-dev' fails, the scripts now create/ensure a venv, install the 'calibreweb' package into it via 'uv pip', and retry 'uv sync' with '--no-build-isolation'. This works around failures caused by isolated builds or build-step issues and preserves existing log messages.
