Mobile declutter pass: step flows, compact cards, simplified settings

Phones only (<=639px); desktop markup is untouched.

- New deck is a 3-step flow: progress (1/3 + bar) and a fixed Back/Next
  bar above the tab bar. Step 1 = Add photos or files / Camera / Paste
  text instead (no drop zone or paste copy on touch), step 2 = folder,
  difficulty and count with defaults plus one collapsed focus/notes row,
  step 3 = one summary line (photos/docs/text · difficulty · count ·
  folder) with Freeze. Going Back keeps every input; step transitions
  respect prefers-reduced-motion.
- Make my homework is a 2-step flow sharing the same pattern; tapping a
  mode card starts it (no separate CTA on phones), with a short preview
  of the assignment on step 2. The hero is now 'Make my homework' /
  'Udělej mi úkol' everywhere ('Solve your homework' is gone) and the
  intro is one line.
- Library: stats line removed, folder row and 'Unorganized' heading
  hidden until folders exist (New folder lives in the drawer), Import is
  a small icon button beside the tabs. Deck and homework cards are
  compact on phones: title, one meta line (activities · difficulty ·
  best), a one-line description that expands on tap, the whole card
  tappable and a small Study/Open pill instead of the full-width button.
- Settings sheet on phones: no .env.local subtitle; Language stays first;
  one Connection card (status dot + 'Connected · 2 models ready', key
  field with the eye inside, Save only when edited, auto re-check on
  save, refresh icon instead of Test connection); privacy one-liner with
  a More expander (daemon tip inside); raw health rows behind one
  collapsed Details list; Remove key as a small danger button at the very
  bottom (same confirmation).
- Decorative orbs on phones moved further off the screen edges so they
  never glow under cards or primary buttons.
- Shared markup for folder/difficulty/count and mode cards keeps one
  source of state; new lib/use-phone.ts gates the layouts.

Verified: new declutter suite 116/116 (360 + 390, EN + CS, photo + PDF +
pasted text, Back keeps input, summaries, settings flow), regression
74/74, mobile 52/52, i18n 25/25. Lint + build clean. SW freezmo-v20.

app/globals.css

@@ -338,12 +338,12 @@ body {
     --ice-blob-opacity: 0.2;
     --ice-orb-opacity: 0.42;
   }
-  /* Tucked up behind the glass header: at top 8% it sat right behind the page
-     heading and subtitle. */
-  .ice-orb-1 { width: 88px; height: 88px; top: -30px; left: -38px; }
-  .ice-orb-2 { width: 72px; height: 72px; left: -32px; }
-  /* Was sitting right behind the bottom-nav labels. */
-  .ice-orb-3 { width: 116px; height: 116px; bottom: 15vh; right: -46px; }
+  /* Phones: orbs hug the screen edges so they can never sit under the
+     content column's cards or primary buttons (the lower-right one used to
+     glow right behind the main CTAs). */
+  .ice-orb-1 { width: 96px; height: 96px; top: -44px; left: -48px; }
+  .ice-orb-2 { width: 72px; height: 72px; top: 60%; left: -44px; }
+  .ice-orb-3 { width: 124px; height: 124px; bottom: 12vh; right: -84px; }
 }
 
 @layer components {