v0.8.0

Built by .github/workflows/release.yml from 3306e41.
Every archive ships a .sha256 beside it.

These builds are not signed or notarized — that needs a paid
Apple Developer account, which this project does not have. So:

• macOS — the download is quarantined and Gatekeeper will refuse
  it. Open it once, let it be blocked, then allow it under System
  Settings → Privacy & Security → Open Anyway. Or build from
  source (wails3 task build), which is never quarantined.
• Windows — unsigned, so SmartScreen warns. "More info → Run
  anyway".
• Linux — nothing to bypass.

See "Running an unsigned build" in docs/README.md for the details,
and "Signing" for the secrets that would make this section
unnecessary.

What's Changed

• Arrive with a picture, and stop paying for it in keyframe interval by @floatdrop in #3
• Give the base layer the highest object IDs, so a joiner keeps receiving it by @floatdrop in #4

Full Changelog: v0.7.2...v0.8.0