Fix missed call site from project group refactor (#52)

This fixes a missed call of `getMyProjectGroups()` in #44 following
rebase of #50 which changed the behavior of the method.

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## Summary

This PR fixes a missed update in the TDEI workspace export page's data
loading logic that was introduced during the project group refactor from
PR `#50` and issue `#44`.

### Changes

**pages/workspace/[id]/export/tdei.vue**

Updated the `Promise.all` call that fetches initial data to properly
handle the API response structure:

- Modified the `getMyProjectGroups()` call to include explicit
pagination parameters: `getMyProjectGroups(1, '', 10000)`
- Updated the destructuring pattern to extract the `items` property from
the response object: `{ items: myProjectGroups }` instead of receiving
the list directly

This aligns with the API contract where `getMyProjectGroups()` returns
an object with structure `{ items: TdeiProjectGroup[], total?: number }`
rather than directly returning an array. The fix ensures that
`eligibleProjectGroups` is computed correctly from the proper array of
project groups, maintaining the role-based export permission checks and
default project-group selection logic.

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Author: cyrossignol

pages/workspace/[id]/export/tdei.vue

@@ -123,9 +123,9 @@ const exporter = new TdeiExporter(tdeiClient, osmClient, context);
 const route = useRoute();
 const workspaceId = Number(route.params.id);
 
-const [workspace, myProjectGroups] = await Promise.all([
+const [workspace, { items: myProjectGroups }] = await Promise.all([
   workspacesClient.getWorkspace(workspaceId),
-  tdeiUserClient.getMyProjectGroups(),
+  tdeiUserClient.getMyProjectGroups(1, '', 10000),
 ]);
 
 const dataGeneratorRole = `${workspace.type}_data_generator`;