fix: load system fonts for OG image text rendering

usvg's default Options creates an empty fontdb, so no fonts are found
for text rendering regardless of what's installed. Load system fonts
into a fontdb::Database and set the default font family to Noto Sans.

Also picks up a formatting change to index.html from a linter.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/moments-api/src/main.rs

@@ -360,7 +360,12 @@ fn render_contributions_png(
     svg.push_str("</svg>");
 
     // Rasterize at 1200x630
-    let tree = resvg::usvg::Tree::from_str(&svg, &resvg::usvg::Options::default())
+    let mut fontdb = fontdb::Database::new();
+    fontdb.load_system_fonts();
+    let mut opts = resvg::usvg::Options::default();
+    opts.fontdb = std::sync::Arc::new(fontdb);
+    opts.font_family = "Noto Sans".to_owned();
+    let tree = resvg::usvg::Tree::from_str(&svg, &opts)
         .map_err(|e| format!("svg parse: {e}"))?;
 
     let mut pixmap =