Pin the canvas height to what is actually visible, and three fixes

Viewport, again — the homescreen app was the case that broke it. Watching for a
signal cannot work there: launched standalone, iOS resolves the CSS viewport once
against a provisional box and never re-resolves it, so no resize, no layout
change, nothing for a ResizeObserver to observe. Only a rotation forced the issue.
So the CSS box is now a proposal: visualViewport says what is really visible and
the height gets pinned in px to match, re-read on every fit — plus a short settle
salvo after launch, since that launch announces nothing.

- The countdown skipped the transition, where overT is parked at 9999 to hold the
  point flow. It read as RESUMING IN 9999 after the first game you ever win.
- Countdown moved off the HUD line into the open, at a readable size.
- A returned shot is a glancing blow now, not a mirror. Reversing the incoming
  line sent every parry straight back up it — into the thrower — so a boss handed
  you a free wound per volley. Contact across the racket face sets the angle:
  dead centre still goes back at him, which is a placement you earn.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

config.js

@@ -84,6 +84,12 @@ export const TUNE = {
   parryArm: 3.4,    // m — an incoming shot this close makes the next tap a SWING instead of a serve
   parryReach: 1.7,  // m — how far off the racket a return still connects (normal volley reach is 1.82)
   parryWindow: 0.2, // s the return window stays open after the tap
+  // A return is a GLANCING blow: contact off the middle of the racket face throws it that many
+  // degrees off straight up-court. Returns used to mirror the incoming line — straight back at the
+  // thrower — so a boss handed you a free wound with every volley. Meeting it dead centre still
+  // sends it back at him; that is now a placement you earn by moving your feet.
+  parryDeflect: 55, // ° of deflection at the edge of the reach
+  parryJitter: 8,   // ° of scatter on top — a bat-away is never surgical
   // ---- chapter bosses: one every bossEvery games, escalating. The racket zombie is demoted to an
   // occasional opponent (racketEvery) so the boss is the only thing that reads as a wall.
   bossEvery: 10,    // games between chapter bosses