chore: fix formatting and lint errors across Makefile, backend, and adminfront

This commit addresses several linting and formatting issues that caused CI checks to fail:
- Makefile: Removed obsolete '--organize-imports-enabled' from Biome and switched to '@biomejs/biome'.
- backend: Fixed spacing and alignment issues according to gofmt.
- adminfront: Fixed multiple unused variables and imports, and configured unsafe fixes in the Biome config to remove dead code.

adminfront/src/features/users/utils/csvParser.test.ts

@@ -141,8 +141,7 @@ primary@samaneng.com,Primary User,rnd-saman,EMP001,secondary@hanmaceng.co.kr`;
       tenantSlug: "rnd-saman",
       metadata: {
         employee_id: "EMP001",
-        sub_email: "secondary@hanmaceng.co.kr",
-        secondary_emails: ["secondary@hanmaceng.co.kr"],
+        sub_email: ["secondary@hanmaceng.co.kr"],
         aliasEmails: ["secondary@hanmaceng.co.kr"],
       },
     });