PackRelay Launcher v0.1.5

Pre-built binaries for the PackRelay launcher.

Windows users: the binary isn't yet code-signed, so
Windows SmartScreen will flag it as an "unrecognized
app" on first run. Click More info → Run anyway.
The launcher is open source — every binary attached to
this release is built by GitHub Actions directly from
this repo's source.

macOS users: the .dmg is signed + notarized — open
normally. (If you happen to land on an older v0.1.x
release that pre-dates this, you'll need to right-click
→ Open the first time.)

See the README for what's in this release.