For normal compilation, use .typelib files rather than .gir XML files.
This is much faster.
Rather than using libgirepository, which would try to actually load the
libraries, we use a custom parser.
The language server will still read XML because it needs to access
documentation, which is not in the typelib, but that's generally fine
because it's a long lived process and only has to do that once.
Install the python module to the data directory, not the python install
directory that meson gives us. Then, in the main script, try to find the
module and add it to the path by assuming the script is installed to
(prefix)/bin. Hopefully this will fix the ModuleNotFound errors.
