fix(web): session-card button overflow + bottom-nav icon alignment

- Dashboard session card: the header stacks the title above the action buttons
  on narrow screens (flex-col -> sm:flex-row) and the button group wraps
  (flex-wrap), so "Request IDR" / "Stop session" no longer overflow the card.
- Mobile bottom nav: give each label a fixed two-line-tall centered box so a
  1- or 2-line label (labels vary by locale) keeps every tab icon at the same
  height.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/components/app-shell.tsx

@@ -80,7 +80,11 @@ export function AppShell({ children }: { children: ReactNode }) {
             activeProps={{ className: 'text-[var(--brand-light)]' }}
           >
             <Icon className="size-5 shrink-0" />
-            <span className="w-full text-center text-[10px] leading-tight">{label()}</span>
+            {/* Fixed two-line-tall box so a 1- or 2-line label keeps every icon
+                at the same height (the labels vary by locale). */}
+            <span className="flex h-7 w-full items-center justify-center text-center text-[10px] leading-tight">
+              {label()}
+            </span>
           </Link>
         ))}
       </nav>