feat(js): m10 extensions (pause, restart, speed-up via Frame) with tests

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

js/solutions/game.js

@@ -1,12 +1,31 @@
 // m05 game: one `update` function turns every action into a new state; replay is a fold over actions.
+// m10 adds pause, restart and a frame clock that speeds up as the score grows.
 import { turn } from './rules.js'
-import { tick } from './spawn.js'
+import { tick, newGame } from './spawn.js'
+
+/** How many frames pass between game steps: 8 at first, one fewer every 3 points, never fewer than 2. */
+export const movesEvery = (score) => Math.max(2, 8 - Math.floor(score / 3))
+
+// One animation frame: count it, and every `movesEvery(score)`-th frame run a game step.
+const frame = (state) => {
+  if (state.status !== 'Playing') return state
+  const counted = { ...state, frame: state.frame + 1 }
+  return counted.frame % movesEvery(counted.score) === 0 ? tick(counted) : counted
+}
+
+// Pause and resume only make sense in those two statuses; a finished game stays finished.
+const togglePause = (state) =>
+  state.status === 'Playing' ? { ...state, status: 'Paused' }
+    : state.status === 'Paused' ? { ...state, status: 'Playing' }
+    : state
 
-/** Tick and Turn are handled here; other actions leave the state alone (m10 adds more). */
 export const update = (state, action) => {
   switch (action.tag) {
     case 'Tick': return tick(state)
     case 'Turn': return turn(state, action.dir)
+    case 'TogglePause': return togglePause(state)
+    case 'Restart': return newGame(state.seed)
+    case 'Frame': return frame(state)
     default: return state
   }
 }