Remove hive submodule and use direct hived image specification

- Remove hive submodule (test-tools is already installed via pip)
- Update CI to include templates from common-ci-configuration directly
- Replace prepare_hived_image jobs with simpler versions that pull
  pre-built images by tag (HIVED_IMAGE_TAG variable)
- Remove TEST_TOOLS_PATH from Dockerfile (unused, test-tools comes from pip)
- Remove freeze-wheel workaround (no more nested pyproject.toml files)

This simplifies CI by:
1. Eliminating complex submodule management
2. Making hived version explicit via HIVED_IMAGE_TAG
3. Reducing docker build context size