Update README: browser layout, iPad/Safari, WebSocket disconnect

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SH2D4LRuCnhLSzoYerAfJX

README.md

@@ -80,6 +80,14 @@ ws/                          Minimal WebSocket pub/sub layer: server
                              (single- and multi-user), client, and a
                              keyed message dispatcher (e.g. "Sensor",
                              "Heater", "TempCtrl", "Stirrer", "Pot", "Sud").
+                             Abrupt client disconnects (no WebSocket close
+                             frame — the normal case for browser tab closes
+                             and Safari session teardowns) are handled
+                             gracefully: `User.send()` catches
+                             `ConnectionClosed` silently, and `handler_recv()`
+                             exits cleanly on it, so a vanishing client never
+                             produces an uncaught exception or "connection
+                             handler failed" log noise.
 
 scripts/demos/               Standalone, eyeballed-plot demos (matplotlib)
                              exercising components/* in isolation — pid/,
@@ -610,6 +618,17 @@ for the desktop app's native file dialogs), Start/Pause/Stop, and Confirm
 (a plain `<dialog>` pops with the step's message on `WAIT_USER` and sends
 Confirm when dismissed) are all wired up.
 
+The page carries a `<meta name="viewport">` tag so Safari and other mobile
+browsers render at device CSS pixels rather than the 980 px virtual layout
+they otherwise default to — essential for touch usability on iPad. The
+header is a two-row layout: the top row holds the host address input,
+Connect button, connection status, and the three large (76 × 76 px)
+circular transport buttons (Start/Pause/Stop) with the countdown to their
+right; the New/Load/Save file buttons occupy their own row directly below.
+The LCD panel (Temperature/Heat rate/Power) uses a four-column grid, with
+unit labels (°C, °C/min, W) in a dedicated column to the right of the Soll
+value rather than embedded in the row labels.
+
 The browser client applies the "state is server-only" principle strictly
 throughout `web/app.js`: every slider, readout, and checkbox is updated
 only when a push arrives from the server, never speculatively on user