Navigation restructure: five-tab bottom bar, no phone drawer

Drawer removed (phones only; desktop rail untouched)
- MobileSidebar, sidebarOpen/useSidebarOpen, MenuIcon and the drawer's
  back-gesture layer are gone; the shared nav content now serves only
  the desktop rail (dead mobile branches deleted). No drawer-specific
  CSS existed; the three drawer strings (header.openMenu,
  sidebar.closeMenu, common.menu) and library.importAria are removed.
- The header drops the hamburger: logo + name on the left, the single
  theme chip on the right.

Five-tab bottom bar
- Library / Progress / New deck (prominent centre +) / Exam / Settings,
  in that order; Progress and Exam reuse the existing /stats and /exam
  screens, Settings keeps opening the dialog. Sliding pill, icon bounce,
  press feedback, re-tap-to-top and safe-area padding kept; every item
  is >=44px (72px wide at 360px).
- New short tab.* keys (EN + CS) so all five labels stay on one line at
  360px — 'Zkouškový režim' became 'Zkouška'. No ellipsis anywhere.
- The bar is mounted once in AppHeader so library, progress, exam and
  share get it; the wizards keep their own bottom action bar and the
  tab bar steps aside there, exactly as before.

Re-homed drawer destinations
- Smart Review card loses the Exam link (it is a tab now); Review due
  and Mistakes stay.
- New deck screen (and /homework) get a Study deck / Make my homework
  segmented switch; the library's homework empty-state button stays.
- The phone import icon becomes a ... button opening a sheet with
  Import JSON and New folder (back-gesture and Escape close it); folder
  chips still appear only once at least one folder exists, and folder
  creation stays in the New deck options step.

Verified: mobile suite 134 checks (no hamburger/drawer, tab order and
44px targets, label matrix at 360/390 x EN/CS x dark/light x reduced
motion, per-tab routing, deep links, Back from every tab, the ... sheet
with folder creation) plus regression 74/74, wizard 83/83, declutter
116/116, animation 8/8, native 35/35, i18n 25/25, phase1 38/38, phase2
43/43, phase3 20/20, freeze-loading 6/6. Key parity 740/740. Lint +
build clean. SW freezmo-v28.

README.md

@@ -54,7 +54,7 @@ no database, no data leaving your machine except the requests you send to Ollama
   the safe area (the tab bar hides inside the wizard), and it is portalled to `<body>` so the
   screen entrance animation can never displace it. The desktop page is unchanged.
 - **Native-feel touches (phones)**: the Android Back gesture closes the topmost layer first
-  (sheet, drawer, actions panel, then one wizard step); deleting a deck shows an *Undo*
+  (sheet, actions sheet, then one wizard step); deleting a deck shows an *Undo*
   toast instead of a confirm; the deck menu can share a deck as JSON through the system share
   sheet (clipboard fallback); content shared from other apps opens a chooser and lands
   pre-filled in either wizard; haptics (Settings → Haptics, on by default) tick on tab
@@ -67,8 +67,8 @@ no database, no data leaving your machine except the requests you send to Ollama
   1 day, then 3, then interval × ease; wrong ones after ten minutes. The Library shows a **Smart
   review** card with the due count, a **Mistakes** count (activities whose latest answer was wrong —
   they clear themselves once answered correctly) and today's **daily goal** progress. A **Progress**
-  screen (drawer) has the day streak, a five-week calendar, accuracy per subject and per deck and
-  the weakest topics. **Exam mode** (drawer) takes one or more decks, a question count and an
+  tab has the day streak, a five-week calendar, accuracy per subject and per deck and
+  the weakest topics. **Exam mode** (its own tab) takes one or more decks, a question count and an
   optional timer, hides hints and shows a per-deck/per-topic breakdown at the end. **Daily
   reminders** appear in Settings only when the server has VAPID keys configured; subscriptions are
   stored as endpoint + keys only, and `node scripts/send-reminders.mjs` (cron/systemd timer) does
@@ -172,9 +172,9 @@ no database, no data leaving your machine except the requests you send to Ollama
 - **Two pools, never mixed**: a **Study Decks** tab (the folder + card library) and a **Homework**
   tab with saved solutions and step-by-step guides — each with its own empty state and call to
   action, and the active tab lives in the URL (`/?tab=homework`)
-- **Phone library, decluttered**: no stats line, the folder row and “Unorganized” heading only
-  appear once folders exist (the drawer has *New folder*), and Import is a small icon button in
-  the tab row. Deck cards shrink to title + one meta line (activities · difficulty · best
+- **Phone library, decluttered**: no stats line, the folder chips and “Unorganized” heading only
+  appear once folders exist, and a **⋯** button next to the pool switcher opens a small sheet with
+  **Import JSON** and **New folder**. Deck cards shrink to title + one meta line (activities · difficulty · best
   score) + a one-line description that expands on tap, with the whole card tappable and a small
   **Study** pill; homework cards match.
 - Decks saved locally with title, subject, folder, activity count, date, play count and best score
@@ -188,10 +188,14 @@ no database, no data leaving your machine except the requests you send to Ollama
 
 **Design**
 
-- **ChatGPT-style shell**: a persistent left **sidebar** (brand, a quiet "New deck" row, a *Folders*
-  list with per-folder counts, Settings/Dark mode pinned to the bottom). It **collapses** to a 68px
-  icon rail (remembered in `localStorage`) and becomes a slide-in **drawer** behind a hamburger on
-  phones; mobile also keeps the frosted header + iOS tab bar
+- **ChatGPT-style shell on desktop, five tabs on phones**: desktop keeps the persistent left
+  **sidebar** (brand, a quiet "New deck" row, a *Folders* list with per-folder counts,
+  Settings/Dark mode pinned to the bottom), which **collapses** to a 68px icon rail (remembered in
+  `localStorage`). Phones have no drawer and no hamburger: a frosted header (logo + theme chip) sits
+  above an iOS-style bottom tab bar — **Library · Progress · New deck · Exam · Settings** — with the
+  New deck button as the prominent centre action and Settings opening the sheet. The wizards keep
+  their own bottom action bar instead of the tab bar, and the in-page segmented switch moves between
+  the deck and homework wizards.
 - **Frosted ice glass, both themes**: light page `#eef5fd` (pale ice) with white glass panels;
   dark page `#0a1120` with `rgba(255,255,255,.06)` glass. Every large surface shares one recipe —
   translucent tint, 24px `backdrop-blur` (16px on phones), a bright 1px rim, an inner top highlight
@@ -209,11 +213,11 @@ no database, no data leaving your machine except the requests you send to Ollama
 - Micro-interactions: 160–200ms colour/transform transitions, `active:scale-[0.985]`, skeleton
   shimmer, hairline hover washes on every row and card
 - **Motion (phones)**: one shared language (`lib/motion.ts`) — every button, card, chip, tab and
-  drawer row scales to 0.96 on press with a spring release; the tab bar, segmented controls and
+  nav row scales to 0.96 on press with a spring release; the tab bar, segmented controls and
   difficulty/size pickers glide their highlight with a shared `layoutId`; wizard steps slide
-  forward and backward and page content enters direction-aware; the Settings sheet and drawer
-  follow the finger and settle on release velocity; library cards fade up in a capped stagger and
-  animate out on delete; score and XP count up; correct answers pulse, wrong ones shake;
+  forward and backward and page content enters direction-aware; the Settings sheet and the library
+  actions sheet follow the finger and settle on release velocity; library cards fade up in a capped
+  stagger and animate out on delete; score and XP count up; correct answers pulse, wrong ones shake;
   `prefers-reduced-motion` collapses everything to short fades. Only transform and opacity
   animate — never blur.
 - **iOS-flavoured PWA**: standalone mode, safe-area insets, bottom tab bar, sheet-style dialogs with
@@ -537,8 +541,8 @@ on Android Chrome a captured `beforeinstallprompt` turns into a real **Install**
 can be reopened any time from **Settings → Install app** (mobile only).
 
 It launches full-screen in standalone mode (no browser chrome), respects the notch/home-indicator
-safe areas, and has an iOS-style bottom tab bar (Library · New deck · Settings) with sheet-style
-dialogs. Android Chrome also offers "Install app" from the ⋮ menu; Freezmo works offline for the
+safe areas, and has an iOS-style bottom tab bar (Library · Progress · New deck · Exam · Settings)
+with sheet-style dialogs. Android Chrome also offers "Install app" from the ⋮ menu; Freezmo works offline for the
 parts that don't need a model.
 
 What's included:
@@ -1018,6 +1022,22 @@ Things I chose while building, with the reasoning:
     phone and desktop check flows, the shorter follow-up with restore, the guide's explain action,
     and the deck hand-off).
 
+43. **Phones navigate with five tabs, not a drawer.** The drawer, its hamburger, its
+    drag-to-close gesture and its back-gesture layer are gone (`MobileSidebar`, `sidebarOpen`,
+    `MenuIcon` and the three drawer strings deleted); the desktop rail is untouched and is now the
+    only consumer of the shared nav content. The bottom bar is **Library · Progress · New deck (the
+    prominent centre +) · Exam · Settings**, keeping the sliding pill, press feedback, re-tap-to-top
+    and safe-area padding. Tab labels use dedicated short `tab.*` keys because the old names
+    (“Zkouškový režim”) can't fit five-up at 360px; the matrix in the mobile suite checks every
+    label against clipping at 360/390, EN/CS, dark/light and with reduced motion on and off. The
+    wizards keep their own bottom action bar, so the tab bar steps aside there, exactly as before.
+    Drawer-only destinations were re-homed: Progress and Exam became tabs, the New deck screen got
+    a **Study deck ⇄ Make my homework** segmented switch (also on `/homework`), and the library's
+    phone row gained a **⋯** sheet with Import JSON + New folder (folder chips still appear only
+    once a folder exists). Verified by the mobile suite (134 checks: no hamburger/drawer, tab order,
+    the label matrix, per-tab routing, deep links, Back from every tab and the ⋯ sheet) plus the
+    other ten standing suites.
+
 36. **The mobile declutter pass reshapes, it doesn't fork.** Phones (≤639px) get a 3-step deck
     flow and a 2-step homework flow that share the exact state and handlers with the desktop
     cards (one `UploadScreen` / one `HomeworkInput`, two layouts switched by `useIsPhone()`);
@@ -1046,7 +1066,7 @@ Things I chose while building, with the reasoning:
     transform on an ancestor becomes the containing block for `position: fixed`, so the bar
     used to paint inside the content and jump to the viewport bottom a second later. It now
     only fades in, pinned to the bottom from its first frame — verified by sampling its
-    position across the entrance (5 frames, 60–450ms) from the tab bar, the drawer and the
+    position across the entrance (5 frames, 60–450ms) from the tab bar, the mode switch and the
     empty state, at 360/390, both themes, both languages and with reduced motion.
 
 39. **Native feel is layered onto the platform, never around it.** The Back gesture closes the
@@ -1059,7 +1079,7 @@ Things I chose while building, with the reasoning:
     Wizard drafts and the last URL are per-browser; the share target hands POSTed files to the
     client through a ten-minute in-memory store so nothing touches disk. Verified by the native
     suite (35 checks: manifest/head/viewport, offline banner + disabled generate, share target GET
-    and POST, back-gesture closing for drawer/sheet/wizard, undo toast, share fallback, tab
+    and POST, back-gesture closing for sheet/wizard, undo toast, share fallback, tab
     re-tap, haptics persistence, draft restore) plus the six standing suites.
 
     **Needs a real device to verify** (emulation can't do these honestly): the iOS hidden-switch