Rasterize glyphs without D2D (#35376)

This allows debugging Zed with Renderdoc, and also fixes an issue where
glyphs' bounds were miscalculated for certain sizes and scale factors.

Release Notes:

- N/A

---------

Co-authored-by: Kate <kate@zed.dev>
Co-authored-by: Julia <julia@zed.dev>
Co-authored-by: Junkui Zhang <364772080@qq.com>

crates/gpui/examples/text.rs

@@ -198,7 +198,7 @@ impl RenderOnce for CharacterGrid {
             "χ", "ψ", "∂", "а", "в", "Ж", "ж", "З", "з", "К", "к", "л", "м", "Н", "н", "Р", "р",
             "У", "у", "ф", "ч", "ь", "ы", "Э", "э", "Я", "я", "ij", "öẋ", ".,", "⣝⣑", "~", "*",
             "_", "^", "`", "'", "(", "{", "«", "#", "&", "@", "$", "¢", "%", "|", "?", "¶", "µ",
-            "❮", "<=", "!=", "==", "--", "++", "=>", "->",
+            "❮", "<=", "!=", "==", "--", "++", "=>", "->", "🏀", "🎊", "😍", "❤️", "👍", "👎",
         ];
 
         let columns = 11;