0.1.3

ci: auto-publish a GitHub Release on every push/merge to main

Previously main pushes only built artifacts and a release was cut on a vX.Y.Z
tag. Now every push to main builds + publishes a Release that electron-updater
consumes. The release version is computed at build time as
<major>.<minor>.<github run number> from desktop/package.json (not committed
back, so no workflow loop), giving distinct, monotonically-increasing versions
for auto-update. Bump major/minor in package.json to start a new line.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>