Fix/sondehub request timeouts

[cartpauj]

Resolve #456

Fix SondeHub timeout issues causing device hangs

Fixes issue where the device would get stuck indefinitely in "Waiting for ACK from server" state when SondeHub requests don't receive responses.

Problem:
The SondeHub client had no timeout mechanism for waiting for server acknowledgments or import responses. If the server didn't respond or the connection was lost mid-request, the device would hang in WAITACK or WAITIMPORTRES states indefinitely, requiring a manual restart.

Solution:

• Added timeout variables for both WAITACK (15 seconds) and WAITIMPORTRES (30 seconds) states
• Implemented timeout checks in the state machine that automatically trigger reconnection
• Different timeout values based on expected response size: smaller for HTTP ACKs, larger for import data
• Proper cleanup of timeout variables on state transitions and error conditions