Mission Run Overview
Mission Run: locate_project_root Split-Brain Consolidation
Eliminate the three-way split-brain in project root resolution so all callers get authoritative env-var and worktree behavior.
Three implementations of locate_project_root exist with divergent behavior: the authoritative one in paths.py (honors SPECIFY_REPO_ROOT and git worktree pointers) and a reduced one in project_resolver.py (plain .kittify walk only) re-exported by core/__init__.py. The four callers of the reduced version silently misresolve in CI/CD environments and git worktrees, causing hard exits, wrong lint working directories, and silent migration-gate bypasses. This mission consolidates all resolution authority into a single code path via a deferred-import delegation shim, plus adds the missing test coverage that would have caught the divergence.