feat(course): audit fixes and twelve extensions (Modules 7b, 12, 13)

Audit pass:
- Frame rule counts frames since the last move, so every step lasts
  exactly movesEvery(score) frames, also right after a speed-up
- clampTime + MAX_GAP_MS: a hidden tab no longer replays the whole gap
- Pong Restart keeps held keys
- Fact corrections (mulberry32 output coverage, Haskell IO, uniform)
- New fixture cases from a mutation analysis

Extensions (all three tracks, shared fixtures, course text):
- Turn queue (Exercise 10.6), persisted high score (10.7),
  replay viewer (10.8), play() end-to-end helper (9.5)
- Optional State (4.7) and optional Module 7b, stack-safe IO
- Module 12, property-based testing with generators, shrinking,
  invariants and a model-based oracle
- Module 13, Conway's Life with a Click event
- JS type checking via jsconfig, JSDoc and types.d.ts
- Maintainer tools: scripts/mutate.mjs, scripts/typecheck-js.sh,
  Playwright end-to-end suite (e2e/, scripts/e2e.sh)

Docs: docs/contract.md is the canonical contract; specs and build log
under docs/superpowers.

Verified: JS 728, Scala 689, F# 691 unit tests; stubs and progression
M01-M13 and M07b; 176 end-to-end tests on Chromium and WebKit.

Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>

js/solutions/life/view.js

@@ -0,0 +1,20 @@
+// m13 life view: live cells as squares, and a status strip under the board.
+import { LW, LH, LCELL, STRIP } from './model.js'
+/** @import { LifeState, Scene, Shape, Align } from '../types' */
+
+/** @type {(x: number, y: number, w: number, h: number, color: string) => Shape} */
+const rect = (x, y, w, h, color) => ({ tag: 'Rect', x, y, w, h, color })
+/** @type {(x: number, y: number, str: string, align: Align) => Shape} */
+const text = (x, y, str, align) => ({ tag: 'Text', x, y, text: str, color: '#ffffff', size: 14, align })
+
+const W = LW * LCELL
+const H = LH * LCELL
+
+/** @type {(state: LifeState) => Scene} */
+export const lifeView = (state) => [
+  rect(0, 0, W, H, '#111111'),
+  ...state.cells.map((p) => rect(p.x * LCELL + 1, p.y * LCELL + 1, LCELL - 2, LCELL - 2, '#7cb342')),
+  rect(0, H, W, STRIP, '#222222'),
+  text(6, H + 17, `Generation ${state.generation}`, 'left'),
+  text(W - 6, H + 17, state.running ? 'Running: Space pauses' : 'Paused: Space runs, N steps', 'right'),
+]