Release v0.1.1 – Safer subscriber loop, graceful shutdown

This patch release hardens the FIFO subscriber loop to make production usage safer and more responsive.

✨ Highlights

• Automatic roll-backs on all error paths
  • fifoSubscriber.Start now rolls back the transaction if box initialization, message processing, or commit fails – preventing dangling or locked DB transactions.

• Graceful shutdown & context awareness
  • The main processing loop now checks ctx.Done() on every iteration and during waits, exiting cleanly when the caller cancels the context.
  • wait helper replaced time.Sleep with a select on <-ctx.Done() to avoid hanging during shutdown.

• Context-aware waiting strategy
  • The wait logic remains the same (different back-off when messages were/weren’t found) but can now be interrupted instantly on shutdown.

🐛 Fixes

• Eliminated potential resource leaks caused by un-rolled-back transactions.
• Removed noisy duplicate log lines when retrying after errors.

🔧 Internal

• Added wait(ctx, cause, d) helper replacing the old blocking wait.
• Incremented code coverage of edge cases in subscriber loop.

No breaking API changes – a recommended drop-in upgrade for all users.