feat(airport): add the Hex Airport dispatch lab as a baseline snapshot

Six-side aprons, frozen levels, solver, rewards and verify scripts; the edge-runway readability work continues from here.

labs/airport/rewards.js

@@ -0,0 +1,12 @@
+// The host adapter must return a completed receipt only after its rewarded-ad
+// success callback. No ad SDK or network service is bundled with this prototype.
+export async function requestReward(game, provider, isCurrent = () => true) {
+  if (game.rewardPending || game.won || game.deadlocked || !isCurrent()) return { status: 'unavailable' };
+  game.rewardPending = true;
+  try {
+    const receipt = await provider({ levelId: game.level.id, steps: game.level.reward.steps });
+    if (!isCurrent()) return { status: 'stale' };
+    return { status: game.grantReward(receipt) ? 'granted' : 'cancelled' };
+  } catch { return { status: 'failed' }; }
+  finally { game.rewardPending = false; }
+}