To avoid duplicating this file across all FSE themes
I'm moving it to the FSE plugin instead and providing
hooking to theme activation there. This is now viable
since we are no longer hardcoding the templates in
themes, but fetching them from the Dotcom API.
We disabled alignment settings for the blocks, but the template
content still has alignment in it. This produces a template
conflict warning in the editor.
This adds required functionality to support rendering FSE header and
footer on all site pages (static and dynamic). It's also includes the
data population functionality, which has now been removed from the plugin
and will be delegated to each theme for maximum flexibility.
