0.1.0

Add Makefile and auto-update via GitHub Releases

Three commands to run and package, all in containers. Windows switches from
portable to NSIS because electron-updater cannot update a portable .exe.

Updates check on launch and every 6h, download in the background and offer a
restart through a toast, so nothing interrupts a broadcast. config.json is read
from userData first, since the NSIS installer rewrites its own directory on
every update and an override next to the .exe would not survive.

Icon regenerated at 256x256, the minimum electron-builder accepts.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>