BAT-008 Planning

Scope

Implement REQ-009: asset_snapshots/manual_assets valuation model, authority-source rule, month-end manual snapshot policy support.
Implement REQ-010: asset snapshot read MCP, net-worth timeseries read MCP, manual assets read MCP, dashboard/MCP alignment.
Preserve REQ-005 safety fallback when new tables are empty.
Use synthetic/temp data only for tests and verification evidence.

dcy-008 confirmed Discovery and approved REQ-009/REQ-010.
Existing REQ-005 dashboard liquidity/net-worth flow and accounts.last_balance authority-source baseline.
Existing MCP server/service pattern in jarca_ledger_mcp/server.py, jarca_ledger_mcp/service.py, jarca_ledger_mcp/db.py.
Additive/idempotent SQLite migration discipline and synthetic-only evidence policy.

Create BAT-008 standard batch docs and register entry.
Add schema/model support for manual_assets and asset_snapshots with safe empty-table fallback.
Add service-layer valuation helpers, snapshot accumulation/report functions, and dashboard alignment logic.
Add read-only MCP tool endpoints/contracts for snapshot read, net-worth timeseries, and manual assets read.
Update baseline docs (docs/data-model.md, docs/interface-contract.md, docs/project-structure.md, docs/runtime-flows.md).
Run narrow validation first (targeted tests / lint / smoke as applicable), then broader regression if narrow gates pass.
If evidence satisfies ACs, move BAT-008 to release-candidate and REQ-009/REQ-010 to Implemented.

Result: standard batch 유지.
Reason: schema, service, MCP contract, dashboard alignment, baseline docs를 함께 변경하며 interface/data/fallback 설계가 필요하다.

Authority-source drift between dashboard and MCP: mitigate by centralizing valuation helpers and writing shared regression tests.
Empty new tables breaking existing REQ-005 flows: mitigate by explicit fallback tests and additive migrations only.
Double counting between account-backed assets and manual assets: mitigate by clearly separating source responsibility and documenting inclusion/exclusion rules.
Snapshot history ambiguity: mitigate by storing basis date, source type, and memo for every snapshot row.