Add request_tip_presence() for hardware-based error recovery

[rickwierenga]

Summary

• Adds request_tip_presence() -> List[Optional[bool]] to LiquidHandlerBackend for querying hardware tip sensors
• Implements it across all backends: STAR, Vantage, Nimbus (hardware query), chatterbox backends (tip tracker), and serializing backend
• Uses it in LiquidHandler.pick_up_tips and drop_tips error handling to determine per-channel success from hardware ground truth, falling back to ChannelizedError info when not available
• Catches BaseException (including KeyboardInterrupt) to ensure state tracking stays accurate

Test plan

• All 52 existing liquid handler tests pass
• Test with STAR hardware: verify request_tip_presence returns correct values after partial pick_up_tips failure
• Test with Vantage hardware: verify query_tip_presence wrapper works
• Test KeyboardInterrupt during pick_up_tips correctly queries tip presence and updates state

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