Add basic pre-commit checks to check and fix issues and conform style

[CAM-Gerlach]

A suite of basic checks using Pre-Commit would be a good idea to add to automatically spot likely errors, bugs, security problems, bad practices, style issues and more. This could also automatically check that commit messages are descriptive and follow the standard format, and commits are signed off.

Pre-commit makes this super easy, just drop in the config file, add the action to the CIs and it takes care of the rest, and it can run both locally with each commit and on CIs, while dramatically reducing the number of nitpicky issues that need to be handled manually in code review. Pre-commit installs, updates and runs the deps and even the runtimes required automatically in isolated environments, to avoid any extra workload to get a dev environment set up aside from running pre-commit install.

I would also take the opportunity to clean up some remaining linting issues and add a few security scanners like Semgrep and CodeQL to the CIs, given this is a web API after all (perhaps in a separate PR), and add the necessary prefab sections to the contributing guide explaining this.