Several tenants have queued work, and a busy tenant must not prevent smaller queues from making progress. Implement the required round-robin dispatch order while preserving each tenant's own queue order.
Build the implementation in Go under /app, with /app/run.sh as its entry point. Read one JSON request from standard input and write one JSON result to standard output. Input has queues mapping tenant names to lists of job IDs and nonnegative integer limit. Repeatedly visit tenant names in sorted order, taking at most one job from each nonempty queue per round. Stop at limit or when all queues are empty. Return dispatched records tenant/job and remaining queues, including empty ones. Preserve job order within each queue. Reject invalid limit.
Reject inputs that violate an explicit validation rule with exit status 2, no standard output, and {"error":"invalid_input"} on standard error. For valid input, exit with status 0. Keep the implementation reusable for new inputs; it must work offline and must not depend on the example data being the only data it receives.
Repair or replace the unfinished /app/run.sh and add source files under /app. Malformed JSON must use the same invalid-input response. Do not read /tests or /oracle from the application.