Handle pre-release & metadata in version numbering

[ethanjli]

We will want to be able to add a pre-release string (e.g. 1.0.0-alpha.1) to our version numbers, and for this to be appropriately handled by the Github Actions workflows. Similarly, we may want to modify our build file naming to make metadata (e.g. build date and/or BOM variant) into the semantic versioning specifications for build metadata. I'd prefer to keep the build date up from the end of the filename, though - so that builds of the same version from different days are kept together by filename sorting.