apply the new design system to the home page: wrap content in a
container/stack shell with a site-header for the logout and today
links, render the texts list as a vertical stack of cards via the
list-cards primitive, and dress the create plan modal with the new
modal/btn classes. js renders each text as an li.card with the
create-plan button preserved so existing cypress hooks (li,
.create-plan, .plan-name, .save-plan, .cancel-plan, ids) keep
matching.
extend app.css with the every-layout style primitives (container,
stack, cluster, center) used to compose page shells, plus a small
component layer: site-header, btn (primary/secondary/danger), card
and card-link, list-cards, modal, error and a few utility classes.
no template changes here - templates start adopting these classes
in the per-page styling commits that follow.
introduce a single shared stylesheet under public/css. this first
section covers a minimal reset, warm/readable design tokens (color,
typography, spacing, radii, shadows), and base element styling for
headings, links, lists, forms, and buttons. layout primitives and
component classes follow in subsequent commits.
