Enhance error handling and messaging for SoapySDR device initialization:
- Add fallback logic to try empty args if device-specific args fail
- Provide detailed multi-line error messages with troubleshooting guidance
- Include suggestions to check SoapySDR plugins and run SoapySDRUtil --probe
- Clarify device lifetime management in struct
- Document why actual streaming not yet implemented (soapysdr 0.3 limitations)
- Note that sdr 0.3 requires FFI or upgrade for streaming support
This helps users diagnose device initialization failures and understand
the current architectural limitations.
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
Signed-off-by: Stan Grams <sjg@haxx.space>
