TIER-2 READ AGENTS.md conductor/workflow.md conductor/edit_workflow.md conductor/tier2/githooks/forbidden-files.txt conductor/tracks/tier2_leak_prevention_20260620/spec.md conductor/code_styleguides/data_oriented_design.md conductor/code_styleguides/error_handling.md conductor/code_styleguides/type_aliases.md before Phase 0 Tasks 0.1, 0.2, 0.4.
Phase 0 of metadata_promotion_20260624. 11 NEW per-aggregate dataclasses added to src/type_aliases.py (CommsLogEntry, HistoryMessage, FileItem, ToolDefinition, SessionInsights, DiscussionSettings, CustomSlice, MMAUsageStats, ProviderPayload, UIPanelConfig, PathInfo) + RAGChunk added to src/rag_engine.py. Metadata: TypeAlias = dict[str, Any] preserved unchanged as the catch-all for collapsed codepaths. Each dataclass has paired to_dict()/from_dict() methods.
11 regression-guard test files created with 5-7 tests each (~70 tests total). All tests PASS.
The existing tests/test_type_aliases.py was updated to reflect the NEW design (CommsLogEntry etc. are now classes, not aliases to Metadata).
Conventions: 1-space indentation, CRLF preserved, no comments.
