Tags: buildwithparallel/reticulum-rnodes

Expand README credits and license info

Replace the simple "Upstream" section with a more detailed "Credits & Upstream" section that acknowledges key contributors (Mark Qvist, Jacob Eva / Liberated Embedded Systems) and the Reticulum project, and calls out NeoPixel contributions and wiring notes. Also add upstream copyright and licensing notes for the RNode firmware, RNode Firmware CE, and the SX1276 driver to clarify provenance and licenses.