Execution Order Probe

Write runProbe(log) — log is a function that records strings. WITHOUT calling log directly except inside the callbacks, schedule exactly this sequence using log: 1. synchronously: log("sync") 2. a microtask: log("micro") (use Promise.resolve().then) 3. a macrotask: log("macro") (use setTimeout with 0) The probe function itself must return the string "scheduled" immediately, and all three logs must have happened by the time the test awaits one 20ms timeout.