[puddly]

I've been running Ziggurat embedded within OpenThread for a few days now both on the ESP32-C6 and straight on an EFR32MG24, both work fine and don't use much RAM, especially with #74.

For ease of testing, OpenThread RCP + Ziggurat firmwares are now built as part of CI. In the future I think we can move this into the Nabu Casa repo once the rate of bugfixes has slowed down.

[Copilot]

🟡 Changes recommended

The omitted UART timeout patches allow inherited CTS/RTS flow control to block EUSART_TX indefinitely when a host stops accepting data, freezing OpenThread and the embedded Ziggurat stack.

1 open issue

• Bound EUSART transmit waits to prevent OpenThread from freezing · New

What changed in this PR

This PR makes embedded Ziggurat easier to test by building downloadable OpenThread RCP + Ziggurat firmware for Home Assistant Connect ZBT-2 in CI.

Changes:

• Adds a CI job to build the Rust library, integrate it into the Silicon Labs firmware builder, and upload firmware artifacts.
• Replaces the BRD2601B development-board manifest with a ZBT-2 manifest.
• Updates setup documentation to distinguish host and embedded deployments and explain ZBT-2 flashing.

File	Description
README.md	Documents host and device setup, firmware downloads, and serial settings.
firmwares/​efr32mg24/​zbt2_ziggurat_rcp.yaml	Adds ZBT-2 hardware configuration and the embedded Ziggurat extension.
firmwares/​efr32mg24/​brd2601b_ziggurat_rcp.yaml	Removes the development-board firmware manifest.
.github/​workflows/​ci.yml	Builds and uploads ZBT-2 firmware artifacts.

_{Review effort: Balanced}