chore(core): cleanup meson build

This updates our meson min version on Windows to 1.0, which means that
we can avoid having Visual Studio on the path, as meson can find it
anyway. With this change, we can eliminate the batch-wrapper for the
build, significantly improving build performance and simplifying the
scripts.

This also adds a change to disable tests for dependency builds of core,
along with the `--no-tests` command line option for doing builds without
tests.

Minor cleanup includes eliminating various warnings from meson.build
files, and standardizing WASM cross-platform build options for Windows.