Add Fence Posts: the playable page and its place in the catalogue, on the rules in `fence-posts/field.js` #304

A new game in the house style, mounted like the other forged games and built on the tested rules in fence-posts/field.js.

Done looks like:

• [ ] fence-posts/index.html draws a meadow staked with posts, the sheep grazing in each pen, the fences built so far, and each claimed pen marked with its owner's flag. Tap between two posts to build there. Arrow keys move a highlight over the unbuilt lengths, and Enter builds. The farmer's turn plays out a length at a time. The page drives the game only through fence-posts/field.js and adds no game rule of its own. The HUD shows sheep and pens for both sides, and each length and each claim is announced through an aria-live region.
• [x] It follows the README Visual rules: a 360x280 canvas, a fixed 30-degree camera, hard shadows screen-right, and ambient motion stopped under prefers-reduced-motion. Your fences and flags differ from the farmer's by pattern (rails or wattle) as well as colour. The canvas aria-label says how to play, and the rules popup is at most four lines. There is a #mute button, and no .mp3 is committed.
• [x] GAMES in shell.js lists it as { id: 'fence-posts', title: 'Fence Posts', blurb: 'Take turns fencing the meadow and claim every pen you close', kind: 'Strategy', input: 'Tap', accent: '#6b8e23', music: false, forged: true }. It has the matching <li> in the root index.html, a place in the README Games table and the list of games without music, and its town building from the GAMES entry. bun scripts/og.mjs has been run.
• [x] rounds.mjs has a scripted round for fence-posts that reaches the end line. serve.test.mjs asserts that /fence-posts/ and /fence-posts/field.js answer 200. playtest.test.mjs passes for the folder, and bun test passes. Any new page test stays inside the per-game test budget the suite already holds to.

Files: fence-posts/index.html, shell.js, index.html, README.md, serve.test.mjs, rounds.mjs, og/. Risk: these appends conflict with other new-game pulls, so rebase on main before pushing. Fits: a builder.

Waits for the rules issue to land on main.

Reviewed pull #335 at its head: ticked It follows the README Visual rules: a 360x280 canvas, a fixed 30-degree camera, hard shadows screen-right, and ambient motion stopped under prefers-reduced-motion. Your fences and flags differ from the farmer's by pattern (rails or wattle) as well as colour. The canvas aria-label says how to play, and the rules popup is at most four lines. There is a #mute button, and no .mp3 is committed.; GAMES in shell.js lists it as { id: 'fence-posts', title: 'Fence Posts', blurb: 'Take turns fencing the meadow and claim every pen you close', kind: 'Strategy', input: 'Tap', accent: '#6b8e23', music: false, forged: true }. It has the matching <li> in the root index.html, a place in the README Games table and the list of games without music, and its town building from the GAMES entry. bun scripts/og.mjs has been run.; rounds.mjs has a scripted round for fence-posts that reaches the end line. serve.test.mjs asserts that /fence-posts/ and /fence-posts/field.js answer 200. playtest.test.mjs passes for the folder, and bun test passes. Any new page test stays inside the per-game test budget the suite already holds to..

Left open after pull #335 landed: 1 unticked item remains (fence-posts/index.html draws a meadow staked with posts, the sheep grazing in each pen, the fences built so far, and each claimed pen marked with its owner's flag. Tap between two posts to build there. Arrow keys move a highlight over the unbuilt lengths, and Enter builds. The farmer's turn plays out a length at a time. The page drives the game only through fence-posts/field.js and adds no game rule of its own. The HUD shows sheep and pens for both sides, and each length and each claim is announced through an aria-live region.). The planner files each as its own issue and closes this one; a person may close it, tick what is done, or say what is left. Until then the crew does not pick it again.

The open box is shipped on main in 76f43b2: fence-posts/index.html draws the meadow, posts, sheep, both sides' fences and flags; tap and arrow-key/Enter building; the farmer's lengths played one at a time (TURN_MS); the HUD shows sheep and pens for both sides; and an aria-live status announces each length and claim. No new work is wanted, so I am closing this.