Fix #813: type can name an installed version of its font

A font library can hold two versions of one family and style (a new
Montserrat-Bold.ttf beside an old montserrat.ttf). The font database kept
only the first one loaded, so type set in the other couldn't be matched
when a PDF or .ai was opened: it came in as outlines. Now every version
loads (the first stays the one family and style resolve to), PDF import
tries the other versions when the glyphs differ, and type set in a version
the family and style alone wouldn't pick names it in CharStyle::font_version
(left out when None, so documents without it are unchanged). Layout,
shaping, the substituted-glyph highlight, Find Font, Package and Document
Info follow it; changing the font clears it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/doc/src/text.rs

@@ -27,6 +27,11 @@ pub struct CharStyle {
     pub font_family: String,
     #[serde(default = "regular")]
     pub font_style: String,
+    /// Which installed version of the font (its version string) when several versions of the
+    /// family and style are installed and the text was set in one the family and style alone
+    /// wouldn't pick (an imported file's type matched to it); None = the one they pick.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub font_version: Option<String>,
     /// Size in points.
     pub size: f64,
     /// Leading in points; None = Auto (120% of size).
@@ -175,6 +180,7 @@ impl Default for CharStyle {
         Self {
             font_family: "Source Sans 3".into(),
             font_style: "Regular".into(),
+            font_version: None,
             size: 12.0,
             leading: None,
             tracking: 0.0,