🧪 Canary builds: try fixes before the next release

[BarutSRB]

OmniWM now has canary builds: automated builds of main that let you try new fixes and features before the next stable release.

• A new canary is published at most once a day, and only when main has changed since the last canary or release.
• Each one is signed and notarized like a regular release, but skips the review a stable release gets, so expect the occasional regression.
• They are listed on the Releases page as prereleases: canary builds

Stable releases are still recommended for everyday use.

Trying a canary

1. Save a copy of ~/.config/omniwm/settings.toml
2. Quit OmniWM, download the newest canary, and replace OmniWM.app in /Applications with the app from its ZIP
3. Relaunch OmniWM. It keeps your existing settings

OmniWM's update check and Homebrew only follow stable releases, so download newer canaries the same way. To go back to stable, quit OmniWM, then run brew reinstall --cask omniwm (Homebrew) or replace the app with the latest release. If stable can't read settings saved by a canary, restore the copy you saved.

Full steps are in the install guide.

Reporting canary bugs

Open an issue as usual and paste the canary's release link in the version field, so I know exactly which build you're on.

Thanks to @Guria for building the canary pipeline (#799)!