hardware: surface modem CRC counter on TCP and USB radios

[yellowcooln]

Summary

This PR exposes modem CRC errors through the TCPLoRaRadio and USBLoRaRadio interfaces in the way pyMC_Repeater already expects.

The modem firmware already includes crc_errors in CMD_STATUS_RESP, but the host-side radio wrappers were not copying that value onto the radio object as crc_error_count.

This change:

• Caches modem crc_errors in both transport drivers
• Exposes crc_error_count on the radio objects
• Refreshes that counter during normal health checks

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Problem

pyMC_Repeater records CRC errors using:

getattr(radio, "crc_error_count", 0)

This already works for local SX1262 radios, but not for pymc_usb modem transports unless the wrapper exposes the same attribute.

Before this PR:

• Modem firmware sent crc_errors in CMD_STATUS_RESP

• get_modem_status() parsed the field correctly

• TCPLoRaRadio and USBLoRaRadio did not expose:

  • radio.crc_error_count

As a result, repeater-side CRC tracking remained at 0 even when the modem itself was reporting CRC errors.

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What Changed

1. Added Cached CRC State to Both Radio Wrappers

Updated:

• src/pymc_core/hardware/tcp_radio.py
• src/pymc_core/hardware/usb_radio.py

New attributes:

• self._crc_errors = 0
• self.crc_error_count = 0

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2. Synced Modem CRC Errors Into the Radio Object

After unpacking CMD_STATUS_RESP, both wrappers now:

• Store status["crc_errors"] in self._crc_errors
• Store status["crc_errors"] in self.crc_error_count

This is the core compatibility fix for repeater integration.

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3. Surfaced CRC Counters in get_status()

Both wrappers now expose:

• "crc_errors"
• "crc_error_count"

This keeps the returned status dictionary aligned with the live cached values.

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4. Refreshed Status During Normal Health Polling

Previously, health polling only refreshed the noise floor.

Now, the periodic health check refreshes:

• Noise floor
• Modem status

This keeps crc_error_count current during normal operation without requiring special polling paths.

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Why This Is the Right Fix

The existing repeater logic already expects a radio-level attribute:

radio.crc_error_count

That means the compatibility boundary belongs inside pyMC_core transport wrappers rather than in repeater itself.

This keeps:

• Repeater logic unchanged
• Transport wrappers aligned with the existing radio interface contract
• Modem-specific status normalized into the standard radio abstraction

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Files Changed

• src/pymc_core/hardware/tcp_radio.py
• src/pymc_core/hardware/usb_radio.py

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Behavior After This PR

When a pymc_usb modem reports CRC errors in CMD_STATUS_RESP:

• TCPLoRaRadio.crc_error_count updates
• USBLoRaRadio.crc_error_count updates
• Repeater storage records CRC error deltas without repeater-side changes
• Existing API/dashboard paths can surface modem CRC history correctly

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Testing

Validated by:

• Patching both wrappers
• Successfully compiling both modules with py_compile
• Running patched pyMC_core against a live repeater install
• Confirming radio objects expose crc_error_count
• Confirming repeater storage and API record modem CRC errors after malformed modem frames were injected

Observed on a live system:

• Modem reported CRC errors
• Repeater database recorded CRC deltas
• Authenticated repeater API returned non-zero CRC totals/history

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Scope

This PR is intentionally narrow:

• No repeater code changes
• No firmware protocol changes
• No repeater API schema changes
• Only pyMC_core transport wrapper behavior changes

This is a compatibility fix so pymc_usb modem transports behave like other radios from the repeater’s perspective.

[yellowcooln]

itk80/pymc_usb#4