Add aria-label to input fields for better accessibility (#39)

Added aria-labels to the password input in `components/PasswordGate.tsx` and the grid columns/gap inputs in `components/DevToolbar.tsx` to provide clear semantic meaning for screen readers.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

components/PasswordGate.tsx

@@ -55,6 +55,7 @@ export default function PasswordGate({ slug, title }: PasswordGateProps) {
             value={password}
             onChange={(e) => setPassword(e.target.value)}
             placeholder="Enter password"
+            aria-label="Enter password"
             className={styles.input}
             autoFocus
             required