Add changeset

Author: danielguillan

.changeset/tall-rivers-smile.md

@@ -0,0 +1,17 @@
+---
+'@primer/react-brand': patch
+---
+
+Added `imageBackgroundColor` support to `RiverAccordion.Visual` for full-bleed visual backgrounds in the gridline variant.
+
+```tsx
+<RiverAccordion variant="gridline">
+  <RiverAccordion.Item>
+    <RiverAccordion.Heading>Heading</RiverAccordion.Heading>
+    <RiverAccordion.Content>Content</RiverAccordion.Content>
+    <RiverAccordion.Visual imageBackgroundColor="subtle">
+      <img src="example.png" alt="Example visual" />
+    </RiverAccordion.Visual>
+  </RiverAccordion.Item>
+</RiverAccordion>
+```