Phase 05: Subagent Codebase Analysis - 05-03: gsd-indexer subagent for file reading and export/import extraction - 05-04: Refactor analyze-codebase Steps 2-3 to use indexer subagent Gap closure addresses context exhaustion during indexing phase (Steps 2-3), not just entity generation (Step 9). Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>