scaffolder: add header with context menu to NFS task page

Adds a Header from @backstage/ui with a kebab menu to the individual task
sub-page in the new frontend system, restoring the ability to show/hide
logs and button bar, as well as start over, retry, and cancel actions.

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
Made-with: Cursor

plugins/scaffolder/package.json

@@ -74,6 +74,7 @@
     "@backstage/plugin-techdocs-common": "workspace:^",
     "@backstage/plugin-techdocs-react": "workspace:^",
     "@backstage/types": "workspace:^",
+    "@backstage/ui": "workspace:^",
     "@codemirror/language": "^6.0.0",
     "@codemirror/legacy-modes": "^6.1.0",
     "@codemirror/view": "^6.0.0",
@@ -81,6 +82,7 @@
     "@material-ui/icons": "^4.9.1",
     "@material-ui/lab": "4.0.0-alpha.61",
     "@react-hookz/web": "^24.0.0",
+    "@remixicon/react": "^4.6.0",
     "@rjsf/core": "5.24.13",
     "@rjsf/material-ui": "5.24.13",
     "@rjsf/utils": "5.24.13",