chore: add declarativeTemplate to export size table

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: janechu

packages/fast-element/SIZES.md

@@ -21,3 +21,4 @@ Bundle sizes for `@microsoft/fast-element` exports.
 | ElementStyles | 1.65 KB | 729 B | 623 B |
 | enableHydration | 42.93 KB | 13.11 KB | 11.79 KB |
 | ArrayObserver | 12.51 KB | 4.45 KB | 4.01 KB |
+| declarativeTemplate | 85.38 KB | 26.13 KB | 23.02 KB |

packages/fast-element/scripts/measure-sizes.js

@@ -28,6 +28,7 @@ const subpathExports = [
     { name: "ElementStyles", path: "@microsoft/fast-element/styles.js", export: "ElementStyles" },
     { name: "enableHydration", path: "@microsoft/fast-element/hydration.js", export: "enableHydration" },
     { name: "ArrayObserver", path: "@microsoft/fast-element/arrays.js", export: "ArrayObserver" },
+    { name: "declarativeTemplate", path: "@microsoft/fast-element/declarative.js", export: "declarativeTemplate" },
 ];
 
 function formatBytes(bytes) {