MERGE_DEFERRED: yes

Worktree: build-w2c02-ai-visibility-panel-b85fe467
SID: b85fe467-9f98-4d18-9060-aad03592205d

Reason: Implementation divergence — worktree's AiVisibilityPanelService uses direct CitationEngineRegistry
injection with build(Site $site) signature. Main checkout implementation was evolved to use
CitationEngineRegistryContract interface for testability (CitationEngineRegistry is final, cannot be
Mockery-mocked without an interface), and build(Site $site, User $user) to enable future per-user
engine resolution. The interface approach is architecturally superior and was validated by 15 tests.
Merging the worktree version would overwrite the improved implementation and break the test suite.

Resolution: W2C-02 functionality committed directly from main checkout as scoped checkpoint.
The worktree commit (9bf3f476f) is superseded by the main checkpoint commit.