docs: drop references to the retired stable branch The stable branch is frozen and no longer offered by the image builder or referenced by any current build path; ciao is the user-facing branch. - Image-Builder.md: branch picker lists master/ciao only (verified live at /api/stats) - Updating-Firmware.md: sysupgrade self-update follows the build branch (master builds pull master, ciao builds and release images pull ciao); raw.githubusercontent URL now points at ciao; SD revert section reworded master<->ciao - VPN:-Wireguard.md: WG is default on master AND ciao since the ciao restore (930bda98d, in the 2026-10-04 release tag) - the old "not included in release images" claim was factually wrong - Streamer-Comparison.md: branch table rewritten for the five current branches (figata/piuma verified from streamer Config.in defaults; figata offers no timps); Wyze v3 Raptor-override example replaced - only the rt5370 variant still pins Raptor, A1N pins None
Streamer coparison