Fix file import during page copy (#1503)

Previously, **all files were downloaded and uploaded again when copying
within the same environment**.

This bug is caused because our deployed projects use the CDN URL for the
fileUrl and the API URL doesn't match the CDN URL

.changeset/many-melons-judge.md

@@ -0,0 +1,10 @@
+---
+"@comet/cms-admin": patch
+---
+
+
+Always use the `/preview` file URLs in the admin application
+
+This is achieved by setting the `x-preview-dam-urls` in the `includeInvisibleContentContext`.
+
+This fixes a page copy bug where all files were downloaded and uploaded again, even when copying within the same environment.

packages/admin/cms-admin/src/common/apollo/links/includeInvisibleContentContext.ts

@@ -8,6 +8,7 @@ export const includeInvisibleContentContext = setContext((request, prevContext)
         headers: {
             ...prevContext.headers,
             "x-include-invisible-content": ["Pages:Unpublished", "Pages:Archived", "Blocks:Invisible"],
+            "x-preview-dam-urls": "1",
         },
     };
 });