Register 'Enter' for login input field

components/HomeContent.tsx

···
 								onChange={(e) =>
 									setAtProtoIdentifier(e.target.value)
 								}
+								onKeyDown={(event) => {
+									if (event.key === "Enter") {
+										loginToATProto();
+									}
+								}}
 								placeholder="Enter your ATProto handle or DID"
 								value={atProtoIdentifier}
 							/>