metaagent session-005: METASTATE + HANDOFF

- All 7 tasks archived (T1-T7 in .agent/archive/tasks/)
- All 7 requests approved and moved to .agent/archive/requests/
- .agent/archive/index.json created
- .agent/context/project-state.md updated (post-refactor snapshot)
- .agent/handoff-summary.md (full summary for next agent)
- .agent/session-summary.md (phase-level summary)
- .agent/roadmap/sources.md (updated priorities)
- .agent/checkpoints.json: handoff=completed

All 8 phases completed: INIT, ANALYSE, ROADMAP, DECOMPOSITION,
EXECUTION, METASTATE, HANDOFF (DESIGN skipped for existing project).

.agent/archive/requests/req-T3.json

@@ -0,0 +1,31 @@
+{
+  "request_id": "req-T3",
+  "task_id": "T3",
+  "title": "Decimal for money",
+  "status": "ready_for_review",
+  "goal": "Точность финансовых расчётов — float → Decimal",
+  "changes": {
+    "summary": "Все денежные поля в domain/ переведены с float на Decimal. CurrencyConverter использует Decimal арифметику с ROUND_HALF_UP до 2 знаков. ForecastService и ScenarioService переписаны для работы с Decimal. assistant.py получил _DecimalEncoder для json.dumps (Decimal → str в JSON).",
+    "commits": ["363d440"],
+    "files_changed": [
+      "domain/account.py, asset.py, currency.py, liability.py, recurring.py, scenario.py, transaction.py",
+      "application/forecast.py, scenarios.py",
+      "infrastructure/ai/assistant.py"
+    ]
+  },
+  "verification": {
+    "tests_passed": "63/63",
+    "decimal_preserved": "100.50 round-trip exact (no float drift)",
+    "json_safe": "Decimal → str via model_dump(mode='json'), back via model_validate",
+    "cf_init_forecast_scenario_works": true
+  },
+  "fulfills_ac": [
+    "Все monetary поля — Decimal",
+    "CurrencyConverter работает с Decimal",
+    "ForecastService арифметика — Decimal",
+    "Excel-sync продолжает работать",
+    "rich.print/f-strings форматируют Decimal",
+    "JSON-сериализация Decimal работает (через pydantic и _DecimalEncoder)",
+    "pytest 63/63"
+  ]
+}