Handle USB timeouts and error states

[malikalhack]

Safe recovery paths, retries, and reporting for I/O errors and timeouts

[malikalhack]

• Reject short USB writes and responses that do not contain the minimum data
  required by the protocol operation.
• Stop each capture-state transaction at its first failed transfer instead of
  issuing the remaining USB operations with invalid state.
• Retry transient timeouts and I/O errors with bounded attempts and delays.
• Stop acquisition immediately when libusb reports that the device was lost.
• Join an acquisition worker before releasing a lost device's USB resources.
• Keep a connected device available for another Start attempt after repeated
  recoverable transfer errors.
• Report recovery, terminal I/O errors, and device loss through application
  states in the status line.
• Removed the temporary poll/error counters and per-cycle stderr diagnostics.
• Verified on physical hardware that unplugging the device during acquisition
  stops acquisition and closes the connection.
• Added periodic presence checks outside acquisition so an unplugged connected
  device is detected and a returned device appears without a manual rescan.
• Removed the redundant manual rescan control and kept the device-disconnected
  status visible until the device returns.