Put a menu in front of the game, with Marvin to explain it

The overlay is a four-stage machine now — splash -> menu -> {courts, tutorial}
— swapped by data-stage while the backdrop and card frame stay mounted, so the
live court never flashes through between screens.

Court tiles SELECT only. Tapping one used to start the match on the spot, which
gave you no way to compare the three and no way back out; START GAME and BACK
are their own buttons now. Headlines are 15px against the 11px body, so a screen
reads as a screen rather than as a list.

The tutorial is a data table: a Marvin pose, an optional picture already in
assets/, and his lines. Seven pages covering tennis, the turn, the slingshot,
the rack and the duel. Marvin is four new frames off x_boymop1 — waving,
pointing, shrugging, and clutching his mop in terror.

The theme no longer starts at boot. A title screen that plays at you before you
have touched it is rude, and the autoplay policy would have held it silent until
that first tap anyway.

Death returns to the menu instead of the title. The reload stays — it is the
honest full reset — and a sessionStorage flag is what picks the stage on the way
back in.

Machine-gun rounds are tennis balls, so they are drawn as balls and take the
perspective. A fixed 4x4 fillRect was exactly as big at the far baseline as at
your feet, which read as square confetti pinned to the screen.

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

assets/_regen_batches.json

@@ -439,5 +439,19 @@
   "check": "loose",
   "subject": "Three frames of the same tennis opponent, drawn as coarse low-resolution pixel art. FIRST a plain standing frame for scale, exactly like the reference. THEN TWO frames of him standing at the baseline BOUNCING A BALL on the ground before serving, with NO ball drawn. Every figure is the SAME man as the reference and the SAME size: RED polo shirt, dark grey shorts, RED cloth headband, blond hair, seen from the FRONT. Same face, same colours, same proportions. His headband is RED, the same red as his shirt \u2014 never white, cream or grey. In both bouncing frames his racket is held out to the side in his RIGHT hand \u2014 which is on the LEFT-HAND SIDE OF THE IMAGE \u2014 and his other arm is stretched DOWN AND OUT to the RIGHT-HAND SIDE OF THE IMAGE, well clear of his body, with the palm open and facing the ground as if patting a ball. CRITICAL: the two bouncing frames are otherwise the IDENTICAL drawing \u2014 same stance, same legs, same head, same racket, same size \u2014 and the ONLY difference between them is the height of that patting hand: in the first it is low, near knee height; in the second it is higher, near his waist. Draw NO ball in any frame.",
   "palette_ref": "o_idle1"
+ },
+ "marvin": {
+  "sprites": [
+   "marvin1",
+   "marvin2",
+   "marvin3",
+   "marvin4"
+  ],
+  "ref_only": [
+   "x_boymop1"
+  ],
+  "anchor": 0,
+  "check": "loose",
+  "subject": "The reference is ONE young ball boy in a WHITE polo shirt and WHITE shorts with brown hair, seen from the FRONT, holding a floor mop. Draw FOUR frames of that SAME boy \u2014 same face, same brown hair, same white kit, same white shoes, same size, same front-facing view \u2014 with a gormless, dim-witted, slightly cross-eyed expression in every frame. THE FOUR FRAMES ARE FOUR DIFFERENT POSES: (1) WAVING hello with his free hand raised beside his head, big goofy open-mouthed grin, the mop standing upright in his other hand; (2) POINTING away to the side with one arm stuck straight out and his mouth open explaining something, mop upright in the other hand; (3) SHRUGGING with both palms turned up and his shoulders hunched, utterly baffled, eyebrows up, the mop tucked under one arm; (4) TERRIFIED \u2014 eyes wide as saucers, mouth open in a yell, both hands clutching the mop up across his chest like a weapon. Each figure stands upright at the same height with both feet on the ground. The whole boy and the whole mop are fully inside the canvas with clear space around them. The canvas contains EXACTLY FOUR figures and no others."
  }
 }