Retrieve the metadata for the given file, including the record it is attached to and its view/download URLs. The file contents are not returned; use /api/cms/documents/{id}/content for that. The required permission depends on the file's link type: person files require Read Files; business files require Limited Write Contributions or Full Write Accounting; batch files require Limited Read Contributions; bank_reconciliation files require Full Read Accounting; group files require being an administrator or member of the group; other link types follow the permissions of the record the file is attached to.