chore: add proper docs links

Author: brettkolodny

src/client/App.tsx

@@ -181,7 +181,7 @@ export const App = () => {
 						Coder
 					</a>
 					<a
-						href="https://coder.com"
+						href="https://coder.com/docs/admin/templates/extending-templates/parameters"
 						target="_blank"
 						rel="noreferrer"
 						className="font-light text-content-secondary text-sm hover:text-content-primary"

src/client/Preview.tsx

@@ -239,7 +239,9 @@ const PreviewEmptyState = () => {
 					</p>
 				</div>
 				<a
-					href="#todo"
+					href="https://coder.com/docs/admin/templates/extending-templates/parameters"
+					target="_blank"
+					rel="noreferrer"
 					className="flex items-center gap-0.5 text-content-link text-sm"
 				>
 					Read the docs