Reset noise floor samples after frequency changes

[RCGV1]

Summary

• Reset RadioLib noise-floor calibration when reconfigure() applies a different effective receiver frequency.
• Keep the change local to RadioLibInterface; all RadioLib chip drivers already call this base reconfigure path before applying chip-specific settings.
• Clear the noise-floor sample throttle timestamp during reset so collection can restart immediately on the new frequency.
• Add test_radio coverage that seeds RadioLib noise-floor state, verifies it is cleared when frequency changes, and verifies it is preserved when frequency is unchanged.

Why this is needed

LoRa config changes do not generally reboot the node. AdminModule::handleSetConfig() explicitly sets requiresReboot = false for LoRa config, then saveChanges() calls MeshService::reloadConfig(), which notifies the radio config observer and reconfigures the radio live. Channel changes also save without reboot and flow through reloadConfig; this matters because the default frequency slot can be derived from the primary channel name.

Testing

• trunk fmt src/mesh/RadioInterface.h src/mesh/RadioInterface.cpp src/mesh/RadioLibInterface.h src/mesh/RadioLibInterface.cpp test/test_radio/test_main.cpp
• ~/.platformio/penv/bin/python -m platformio test -e native-macos -f test_radio: 17 passed
• pio run -e heltec-v3: SUCCESS

Notes

• Attempted ~/.platformio/penv/bin/python -m platformio test -e native -f test_radio on macOS, but it failed before test execution because LovyanGFX includes Linux-only <malloc.h>. The repo has native-macos for this case, and that target passed.

[github-actions]

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Warning

This is an automated, unreviewed CI test build. Back up your device configuration
before flashing, and only flash devices you are able to recover.

Supported boards built by this PR (22)

	Device	Board	Platform
	Crowpanel Adv 3.5 TFT	elecrow-adv-35-tft	esp32-s3
	Heltec HT62	heltec-ht62-esp32c3-sx1262	esp32-c3
	Heltec Mesh Node 096	heltec-mesh-node-t096	nrf52840
	Heltec Mesh Node T1	heltec-mesh-node-t1	nrf52840
	Heltec Mesh Node T114	heltec-mesh-node-t114	nrf52840
	Heltec V3	heltec-v3	esp32-s3
	Raspberry Pi Pico	pico	rp2040
	Raspberry Pi Pico W	picow	rp2040
	RAK WisBlock 11200	rak11200	esp32
	RAK WisBlock 11310	rak11310	rp2040
	RAK3312	rak3312	esp32-s3
	RAK WisBlock 4631	rak4631	nrf52840
	Seeed Xiao NRF52840 Kit	seeed_xiao_nrf52840_kit	nrf52840
	Seeed SenseCAP Indicator	seeed-sensecap-indicator-tft	esp32-s3
	Seeed Xiao ESP32-S3	seeed-xiao-s3	esp32-s3
	Station G2	station-g2	esp32-s3
	Station G3	station-g3	esp32-s3
	LILYGO T-Deck	t-deck-tft	esp32-s3
	LILYGO T-Echo	t-echo	nrf52840
	LILYGO T-Echo Plus	t-echo-plus	nrf52840
	LILYGO T-Impulse Plus	t-impulse-plus	nrf52840
	Seeed SenseCAP T1000-E	tracker-t1000-e	nrf52840

Build artifacts expire on 2026-07-22. Updated for 9604fe5.

[thebentern]

This probably should target master

[thebentern]

Now that it targets master, it needes to be rebased. We don't want to merge develop into master yet