Resolves #45220 Here's one example why this is a good idea. On `main`, the fleet production binary contains a private key used for testing: ``` $ strings ./build/fleet | rg "BEGIN RSA TESTING" proto3-----BEGIN RSA TESTING KEY----- ``` And it's gone when using this branch: ``` $ strings ./build/fleet | rg "BEGIN RSA TESTING" <empty> ``` ## Testing - [X] QA'd all new/changed functionality manually. <!-- This is an auto-generated comment: release notes by coderabbit.ai --> ## Summary by CodeRabbit * **Chores** * Reorganized and centralized SCEP test helpers and servers for certificate enrollment tests. * Added embedded HTML fixtures to better emulate SCEP/NDES admin responses (cache/full, permissions, password). * Standardized UTF‑16 handling for test responses and improved test server response handling. <!-- review_stack_entry_start --> [](https://app.coderabbit.ai/change-stack/fleetdm/fleet/pull/45619?utm_source=github_walkthrough&utm_medium=github&utm_campaign=change_stack) <!-- review_stack_entry_end --> <!-- end of auto-generated comment: release notes by coderabbit.ai -->