Add Pineapple Portal Golf — two-player grid flicking game with portal holes

[msfeldstein]

What this is

A self-contained two-player web game in portal-golf/ (plain HTML/CSS/JS, no dependencies, no build step — just open portal-golf/index.html or serve the folder statically).

Chaos mode gameplay with revealed portals
Turn-based mode with mystery portals

Rules

• A grid board with scattered walls, three pairs of sibling portal holes, and a gold 🍍 target hole. Boards are randomly generated (with validation that holes/target stay reachable and home columns stay clear).
• Each player (Pink vs Cyan) has 5 balls. Swipe a ball in a direction and it slides until it hits a wall or another ball (stops in the cell before), a portal hole (falls in and pops out resting at its sibling hole), or the target hole (captured, scores a point).
• A ball resting in a hole plugs it: incoming balls roll straight over the paired hole instead of teleporting, and block arrivals at the plugged hole like any other ball.
• First player to sink 3 balls into the target hole wins.

Modes and options

• Turn-based: alternate flicks; input locks while a ball is rolling, and a throw straight into an adjacent wall/ball is rejected so it doesn't waste a turn.
• Chaos: no turns — both players flick their balls as fast as they can, simultaneously.
• Portals: Revealed / Mystery: revealed mode colour-codes sibling holes and draws dashed links between them; mystery mode makes every hole look identical so you learn the pairings by playing.

iPad / touch support

• Pointer-events based input with per-pointer tracking, so two players can aim and throw at the same time on one screen (multitouch).
• touch-action: none, viewport pinned, iOS gesture/double-tap-zoom suppression, and safe-area insets so it plays cleanly full-screen on an iPad.
• Aim arrows render while dragging; works with a mouse on desktop too.

Testing

• 14 headless rule tests (sliding, wall/ball/edge collisions, teleporting, hole plugging and pass-over, target capture and scoring, throw rejection, turn handover, win at 3, chaos head-on collisions, throwing a ball off a hole it's plugging, and validity of 100 random boards) — all pass.
• Driven end-to-end in headless Chrome with real touch-swipe events (both players, both modes, off-turn grab rejection, turn switching) — all pass, no console errors.

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