feat(web): full desktop layout instead of a stretched phone view

- focus screens: question and context on the left, answers on the right in
  one wide card; consent text and the 0–10 scale in one wide column
- today: dashboard with tasks, this week's doses and quick actions side by
  side; meds / doctor / profile in two-column grids; welcome gets «Как это
  работает» steps
- fix: 0–10 scale no longer overflows narrow containers

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/screens/Welcome.tsx

@@ -46,6 +46,23 @@ export function Welcome() {
           </button>
         </div>
 
+        <section className="how" aria-labelledby="how-title">
+          <h2 id="how-title" className="h3">
+            {t.howTitle}
+          </h2>
+          <ol className="how__list">
+            {t.how.map((step, i) => (
+              <li key={step.title} className="how__item">
+                <span className="how__num">{i + 1}</span>
+                <span>
+                  <span className="how__title">{step.title}</span>
+                  <span className="how__text">{step.text}</span>
+                </span>
+              </li>
+            ))}
+          </ol>
+        </section>
+
         <p className="muted small">{t.disclaimer}</p>
       </div>
     </AppShell>