fix: update display shield documentation for clarity and consistency

- Revised text to clarify how the micro:bit fits into the display shield.
- Capitalized "D-pad" for consistency in terminology.

Author: thomasjball

.astro/data-store.json

@@ -6,8 +6,7 @@ description: How to work with the display shield
 ## Working with the display shield
 
 Once you have downloaded the app to your micro:bit, plug it into the display shield.
-See the [display shield overview](/getting-started/display-shields/) to see how
-the micro:bit fits into the shield.
+See below for how the micro:bit slots into the shield.
 
 Most display shields have a built-in battery. Turn on the power switch on the display 
 shield to power both the shield and the micro:bit.
@@ -17,9 +16,9 @@ or the display shield.
 
 ## User interface 
 
-The display shields have a 4-way directional pad (d-pad) or 4 buttons
+The display shields have a 4-way directional pad (D-pad) or 4 buttons
 arrange in a diamond, to the left of the screen.  To the right of 
-the screen are the A and B buttons.  The d-pad is used to move 
+the screen are the A and B buttons.  The D-pad is used to move 
 the cursor in the UI up/down/left/right. The A button is used to
 select the current element the cursor is on. The B button is used
 to back out of a screen or dialog.