Add Bunting: the playable page and its place in the catalogue, on the rules in `bunting/line.js` #190

A new game in the house style, mounted like the other forged games, built on the tested rules in bunting/line.js.

Done looks like:

• [ ] bunting/index.html draws the village green, its posts and lamps, the strings between them and the flags on each hook, with clashing neighbours marked, and drives it only through bunting/line.js; it adds no game rule of its own. Tap a hook to cycle its pattern, or move with the arrow keys and press 1-4. Ambient motion only in the bunting stirring in the wind. The HUD shows level, moves and clashes left as the rules state reports them.
• [ ] Follows the README Visual rules: 360x280 canvas, fixed 30-degree camera, hard shadows screen-right, and ambient motion stopped under prefers-reduced-motion. Each pattern differs by shape as well as colour, so it can be played without telling colours apart, and a clash is marked by a line as well as a colour. The canvas aria-label says how to play. The rules popup is at most four lines. There is a #mute button and no .mp3 is committed.
• [ ] Listed in GAMES in shell.js as { id: 'bunting', title: 'Bunting', blurb: 'Hang the flags for the fete so no two neighbours match', kind: 'Strategy', input: 'Tap', accent: '#3d7f6e', music: false, forged: true }. It has the matching <li> in the root index.html, a building in the town from town.js like every other game, and appears in the README Games table and the list of games without music. bun scripts/og.mjs has been run.
• [ ] rounds.mjs has a scripted round for bunting that reaches the end line. serve.test.mjs asserts that /bunting/ and /bunting/line.js answer 200. playtest.test.mjs passes for the folder, and bun test passes.

Files: bunting/index.html, shell.js, index.html, town.js if buildings are listed there, README.md, serve.test.mjs, rounds.mjs, og/. Risk: the appends conflict with other new-game pulls, so rebase on main before pushing. Fits: a builder.