Graywolf RXT test build 157a4056

Improves TM-D700 and TM-D710/G initialization with mode stabilization and an optional RF packet-speed setting.

After selecting PACKET mode, Graywolf waits four seconds before continuing, even if the command prompt appears earlier. This allows firmware to finish restoring its saved settings.

In a model-specific Serial or USB Serial TNC interface, Radio packet speed offers Preserve radio setting / Conserver, 1200, or 9600. This is independent of the PC serial Baud Rate. When a speed is selected, Graywolf applies HBAUD and reads it back before entering KISS. A refusal or mismatch fails initialization and triggers retries.

Existing interfaces default to Preserve: no HBAUD command is sent, and the firmware's restored speed remains in use. Native KISS and the legacy Kenwood profile retain their existing behavior. Restart Graywolf after upgrading and refresh the browser.

Validation passed: late firmware-restore simulations, HBAUD verification and refusal tests, configuration upgrade, API persistence, race checks, browser selection, 581 web tests, and Linux virtual serial ports using the real serial driver. Physical radio validation is still required.

The Linux amd64 modem build is pinned to the glibc 2.35 baseline, with an automated runtime compatibility check, to avoid requiring glibc 2.43 from a newer build runner.

Documentation: Kenwood setup.

Commit: 157a405. Base version: 0.14.14. RXT pre-release for testing. No OCI images; GHCR latest unchanged.