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>

fsharp/solutions/Life/View.fs

@@ -0,0 +1,17 @@
+/// m13 life view: live cells as squares, and a status strip under the board.
+module Snake.Life.View
+
+open Snake.View
+open Snake.Life.Model
+
+let private text x y str align = Text(x, y, str, "#ffffff", 14, align)
+
+let private W = LW * LCELL
+let private H = LH * LCELL
+
+let lifeView (state: LifeState) : Scene =
+    [ Rect(0, 0, W, H, "#111111") ]
+    @ (state.Cells |> List.map (fun 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) (if state.Running then "Running: Space pauses" else "Paused: Space runs, N steps") "right" ]