Build the Jetty response from exact lines

[adamtheturtle]

The mock preserves Vuforia's exact missing-Content-Type HTML response, including a long <meta> line. Keeping that response in one triple-quoted literal required an E501 suppression.

Build the same byte-for-byte text from adjacent string literals instead. This keeps the wire response exact while removing the line-length exemption.

Validation:

• byte-for-byte response comparison against the existing expected response
• all configured pre-commit, pre-push, and manual hooks
• full non-real suite: 1,957 passed, 833 skipped
• local combined non-real coverage exercised the changed module at 100%; the repository-wide 100% gate requires the configured hosted real/skip/Windows coverage partitions

[adamtheturtle]

The exact-head Test workflow is terminal. The only root failures are the real-Vuforia TestSuccess and TestIncludeTargetData jobs, both receiving 403 ProjectSuspended; current main at d9d675b685da4d248416745db6bd21977046f34f has the same two failures. Combine & check coverage passed at 100%.