apply the page shell to the text detail page and add a scoped
.node-tree style block to app.css. the tree dom rendered by text.js
must keep ul/li with buttons and inputs as direct children of each
li (cypress relies on > selectors), so styling is applied entirely
via descendant selectors without wrapping the rendered nodes.
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.