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>

scala/test.sh

@@ -1,10 +1,19 @@
 #!/usr/bin/env bash
 # Usage: ./test.sh [MNN]   (no arg = all tests)
+# A module tag selects exactly that module's test files: test/MNN<Upper>*.test.scala, so M07 runs M07IO but not
+# M07bSafeIO, and M07b runs only M07bSafeIO. Each file gives one munit glob, `*<file name>*`, matching its suite.
 set -euo pipefail
 cd "$(dirname "$0")"
 SCALA_CLI="${SCALA_CLI:-$(command -v scala-cli || echo "$HOME/.local/bin/scala-cli")}"
 if [ $# -ge 1 ]; then
-  exec "$SCALA_CLI" test src test project.scala -- "*$1*"
+  globs=()
+  for f in test/"$1"[[:upper:]]*.test.scala; do
+    [ -e "$f" ] || continue
+    name="$(basename "$f" .test.scala)"
+    globs+=("*$name*")
+  done
+  [ ${#globs[@]} -gt 0 ] || globs=("*$1*")   # no test file for this tag: keep the old behaviour
+  exec "$SCALA_CLI" test src test project.scala -- "${globs[@]}"
 else
   exec "$SCALA_CLI" test src test project.scala
 fi