feat(evaluation): add source-backed execution profile registry

[daniele21]

Summary

Adds the canonical execution-profile registry needed by EVAL-U-13 and runner preflight without inventing ad-hoc profile values.

• derives evaluation profile refs and generation semantics directly from versioned Qwen35GenerationProfiles;
• pairs every profile with the versioned Qwen3.5 runtime tuning source and exposes its CANDIDATE/MEASURED evidence status;
• requires an explicit product composition tier resolver instead of guessing model tier from filename/size;
• adds registry lookup and a preflight adapter that fails closed with UNSUPPORTED_EXECUTION_PROFILE;
• covers source identity, direct/non-thinking and thinking semantics with focused tests.

The current Qwen3.5 runtime tuning remains candidate evidence; this PR exposes that truth rather than certifying it as measured.