[TASK] Run Sphinx build with warnings treated as errors

[daeyoung-jeong-lge]

Task Description

Run Sphinx build with warnings treated as errors.

Checklist

• Draft run sphinx build with warnings treated as errors design content
• Check consistency with VEL architectural boundaries
• Identify related FR/SEC/SAF requirements

Related Requirement

Part of FEATURE #108

Implementation Guidelines

Keep the design aligned with the Vehicle Evidence Layer scope. Do not introduce coordination, lifecycle execution, process/container/hardware control, policy decisions, or final OEM vehicle decisions.

Testing Method

Review the detailed design for consistency with the architecture and mapped requirements.