Type: Highlight Substituted Fonts moves to Preferences › Type and applies to every document

Highlight Substituted Fonts is now a preference in Preferences › Type,
next to Highlight Alternate Glyphs, on by default and saved with the
other preferences (`prefs.set highlightSubstitutedFonts`). The canvas
reads it through `RenderOptions::highlight_substituted_fonts` for every
open document; a document's own setup no longer decides it. File ›
Document Setup no longer shows the checkbox and keeps Highlight
Substituted Glyphs.

A file saved with Document Setup's Highlight Substituted Fonts off now
shows the pink highlight when it opens, while the preference is on.
The file still opens with the stored value, and saving it again keeps
that value.

`document.setup` no longer reports `highlightSubstitutedFonts`. It
ignores the key and adds a `warnings` entry that names `prefs.set` to
its reply, so an older reply passed back still applies its other keys.

The raster cache of type under a raster effect now also redraws when
Highlight Alternate Glyphs changes.

crates/engine/src/tests_docsetup.rs

@@ -288,6 +288,48 @@ fn setup_survives_save_and_load() {
     assert_eq!(back.setup.grid_colors_name(), "Custom");
 }
 
+/// Highlight Substituted Fonts is a preference (Preferences › Type): `document.setup` does not
+/// report it, and ignores it with a warning that names `prefs.set`, so an older build's reply
+/// passed back still applies its other keys. The document's stored value and the preference stay.
+#[test]
+fn highlight_substituted_fonts_is_ignored_with_a_pointer_to_the_preference() {
+    let mut s = session();
+    let q = s.execute("document.setup", &json!({})).unwrap();
+    assert!(q.get("highlightSubstitutedFonts").is_none() && q.get("warnings").is_none(), "{q}");
+    let r = s.execute("document.setup", &json!({"highlightSubstitutedFonts": false, "bleed": 9})).unwrap();
+    let w = r["warnings"][0].as_str().unwrap_or_default();
+    assert!(w.contains("prefs.set") && w.contains("highlightSubstitutedFonts"), "{r}");
+    assert_eq!(setup(&s).bleed, [9.0; 4]);
+    assert!(setup(&s).highlight_substituted_fonts, "the stored value is not changed");
+    assert!(s.prefs.highlight_substituted_fonts, "nor is the preference");
+    assert_eq!(s.doc().unwrap().history.undo.len(), 1);
+    // The reply, warning included, can be passed back; alone, the key changes nothing.
+    let mut plain = r.clone();
+    plain.as_object_mut().unwrap().remove("warnings");
+    assert_eq!(s.execute("document.setup", &r).unwrap(), plain);
+    assert_eq!(s.execute("document.setup", &json!({"highlightSubstitutedFonts": true})).unwrap()["warnings"], r["warnings"]);
+    assert_eq!(s.doc().unwrap().history.undo.len(), 1);
+    let e = s.execute("document.setup", &json!({"highlightSubstitutedFonts": 1})).unwrap_err().to_string();
+    assert!(e.contains("true or false"), "{e}");
+}
+
+/// A file saved with Document Setup's old Highlight Substituted Fonts value opens, keeps that
+/// value when saved again, and leaves the preference as it was.
+#[test]
+fn a_file_with_the_old_highlight_substituted_fonts_value_opens_and_keeps_it() {
+    let mut s = session();
+    let mut d = (*s.doc().unwrap().doc).clone();
+    d.setup.highlight_substituted_fonts = false;
+    let data = vectorcraft_format::base64_encode(&vectorcraft_format::save_file(&d));
+    s.execute("document.open", &json!({"name": "old.vectorcraft", "dataBase64": data})).unwrap();
+    assert!(!setup(&s).highlight_substituted_fonts);
+    assert!(s.prefs.highlight_substituted_fonts, "the preference decides the screen");
+    let again = vectorcraft_format::load(&vectorcraft_format::save_file(&s.doc().unwrap().doc)).unwrap();
+    assert!(!again.setup.highlight_substituted_fonts);
+    let q = s.execute("document.setup", &json!({})).unwrap();
+    assert_eq!(s.execute("document.setup", &q).unwrap(), q);
+}
+
 /// A file whose bleed, superscript, subscript or small caps size lies outside the range
 /// `document.setup` takes opens with it at the nearer end of that range, and the setup it reports
 /// can be fed back.