Introduce Dockerization

Simplify Docker setup + CI improvements

I'm helping a friend set up their IDE on Windows to get this project compiling — and wow, it's not fun.
Along the way, I realized that the current setup could really use some cleanup and more guidance.

Run git submodule update --init --recursive first on freshly cloned repo.

Dockerization

• Added a Dockerfile based on ubuntu:24.04 to make the dev environment reproducible
• Pinned all packages to their functioning version tag resulting in fully-reproducible builds
• Installed the required packages (GCC 14, Python 3.11 (pinned), Boost, Eigen, etc.)
• Installed CMake >3.29 manually to match project requirements
• Added support for installing Python dependencies from CMake
• Set up the Docker image to be CI-friendly

CI/CD

• Please enable repo runners so the image can actually be built automatically in the future
• I've added a CI check in .gitlab-ci.yml to verify that PRs don’t break the build

Let me know if anything should be changed or if you'd like to tweak the base image/tools.