Release v0.17.0 · fadion/schemaic

Schemaic v0.17.0 — macOS support, on Apple Silicon.

Highlights

Schemaic runs on macOS. A .dmg to drag into /Applications, or a .pkg
if you'd rather have an installer — both update themselves from then on. The
one-line installer handles it too:
```
curl -fsSL https://raw.githubusercontent.com/fadion/schemaic/main/install.sh | bash
```
Apple Silicon only; there is no Intel build. The app isn't signed with an
Apple Developer ID, so a .dmg downloaded in a browser needs one trip through
System Settings → Privacy & Security → Open Anyway the first time. The
installer script above avoids that entirely, and not by weakening anything —
macOS quarantines what a browser downloads, and curl doesn't set that flag.

Treat this one as a preview. It compiles on macOS and the full test suite
passes there, but no one has yet sat in front of it on a Mac. The window
frame — where macOS keeps its traffic lights and Schemaic draws its own header
around them — is the most likely thing to look wrong. Please report anything
that does.

Windows and Linux builds are unchanged.