Fix `visual_bounding_rect` for rotated text (#7050)

TextShape.visual_bounding_rect was not taking the text rotation into
account. I manually tested drawing the new bounding box on top of the
text for various rotations & anchor settings. For example:
<img width="191" alt="image"
src="https://github.com/user-attachments/assets/56528fc7-7e7d-45af-b92a-c1cd307ff205"
/>

The unit test I added will fail without this patch, but perhaps doesn't
add much value.

* [x] I have followed the instructions in the PR template

crates/epaint/src/shapes/text_shape.rs

@@ -59,7 +59,10 @@ impl TextShape {
     /// The visual bounding rectangle
     #[inline]
     pub fn visual_bounding_rect(&self) -> Rect {
-        self.galley.mesh_bounds.translate(self.pos.to_vec2())
+        self.galley
+            .mesh_bounds
+            .rotate_bb(emath::Rot2::from_angle(self.angle))
+            .translate(self.pos.to_vec2())
     }
 
     #[inline]
@@ -154,3 +157,38 @@ impl From<TextShape> for Shape {
         Self::Text(shape)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{super::*, *};
+    use crate::text::FontDefinitions;
+    use emath::almost_equal;
+
+    #[test]
+    fn text_bounding_box_under_rotation() {
+        let fonts = Fonts::new(1.0, 1024, FontDefinitions::default());
+        let font = FontId::monospace(12.0);
+
+        let mut t = crate::Shape::text(
+            &fonts,
+            Pos2::ZERO,
+            emath::Align2::CENTER_CENTER,
+            "testing123",
+            font,
+            Color32::BLACK,
+        );
+
+        let size_orig = t.visual_bounding_rect().size();
+
+        // 90 degree rotation
+        if let Shape::Text(ts) = &mut t {
+            ts.angle = std::f32::consts::PI / 2.0;
+        }
+
+        let size_rot = t.visual_bounding_rect().size();
+
+        // make sure the box is actually rotated
+        assert!(almost_equal(size_orig.x, size_rot.y, 1e-4));
+        assert!(almost_equal(size_orig.y, size_rot.x, 1e-4));
+    }
+}