docs: fix UiFramework external reference

Update the UiFramework external reference to point at the RePebble Layers guide.

Remove the stale Graphics chapter mention from the applib docs.

Co-authored-by: GPT-5 Codex <codex@openai.com>
Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>

Author: gmarull

sdk/docs/external_refs/UiFramework.html

@@ -14,4 +14,4 @@
  limitations under the License.
 -->
 
-<a href="https://developer.getpebble.com/guides/pebble-apps/display-and-animations/layers/">User Interface Layers chapter in the Pebble Developer Guides</a>
+<a href="https://developer.repebble.com/guides/user-interfaces/layers/">User Interface Layers chapter in the Pebble Developer Guides</a>

src/fw/applib/graphics/graphics.h

@@ -27,7 +27,7 @@ typedef struct FrameBuffer FrameBuffer;
 //! are documented below.
 //! See \ref GraphicsContext for more information about the graphics context.
 //!
-//! Refer to \htmlinclude UiFramework.html (chapter "Layers" and "Graphics") for a
+//! Refer to \htmlinclude UiFramework.html (chapter "Layers") for a
 //! conceptual overview of the drawing system, Layers and relevant code examples.
 //!
 //! Other drawing functions and related documentation: