wrap the today page in the shared header + container/stack shell,
render scheduled nodes as cards via list-cards, and add a muted
empty-state message that toggles when no nodes are scheduled.
existing #scheduled-nodes-list and li selectors used by cypress
tests are preserved (the empty message lives in its own element).
add a stylesheet link and the standard responsive viewport meta tag
to every page template. purely additive - no markup or selector
changes - so existing cypress assertions and page js id hooks remain
intact. with this commit every page picks up the base styling from
app.css.