feat(js): m05 game and m06 view with fixtures and tests

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

js/test/m05-game.test.js

@@ -0,0 +1,26 @@
+import test from 'node:test'
+import assert from 'node:assert/strict'
+import { update, replay, history } from '../src/game.js'
+import { loadFixture, freeze } from './helpers.js'
+
+const fixtureTests = (name, f) => {
+  const fx = loadFixture(name)
+  fx.cases.forEach((c) =>
+    test(`m05 ${fx.function}: ${c.name}`, () => assert.deepStrictEqual(f(...freeze(c.args)), c.expected)))
+}
+
+fixtureTests('m05-update', update)
+fixtureTests('m05-replay', replay)
+fixtureTests('m05-history', history)
+
+test('m05 history has one more state than there are actions', () => {
+  const [state, actions] = loadFixture('m05-replay').cases[0].args
+  assert.equal(history(freeze(state), freeze(actions)).length, actions.length + 1)
+})
+
+test('m05 history starts at the start state and ends where replay ends', () => {
+  const [state, actions] = freeze(loadFixture('m05-replay').cases[0].args)
+  const states = history(state, actions)
+  assert.deepStrictEqual(states[0], state)
+  assert.deepStrictEqual(states[states.length - 1], replay(state, actions))
+})