chore: clean up post-refactor — remove old package paths, gitignore .omo/

- Remove old top-level packages (now in domain/application/infrastructure):
  - ai/ (moved to infrastructure/ai/)
  - cashflow_model/ (moved to domain/)
  - cli/ (moved to infrastructure/cli/)
  - engine/ (moved to application/)
  - sync/ (moved to infrastructure/repositories/excel_repository.py)
- .gitignore: add .omo/ (opencode local state)
- AGENTS.md: already updated to MetaAgent v3.0 paths in T1
- data/model.json: SCHEMA_VERSION=1 added in T1

data/model.json

@@ -3,20 +3,20 @@
   "base_currency": "RUB",
   "accounts": [
     {
-      "id": "0283653e-2ebd-48fe-8b64-90ead1804e60",
+      "id": "633c38bd-acdf-4e40-b7ef-64188e3a741d",
       "name": "Основной",
       "currency": "RUB",
-      "balance": 50000.0
+      "balance": "50000.0"
     }
   ],
   "transactions": [],
   "recurring": [],
   "assets": [
     {
-      "id": "a4557779-4bb7-4b3b-b88e-1e436c3e6e43",
+      "id": "d15f81dd-8235-4f93-8452-ba0db359d843",
       "name": "Акции",
-      "value": 100000.0,
-      "growth_rate": 8.0
+      "value": "100000.0",
+      "growth_rate": "8.0"
     }
   ],
   "liabilities": [],
@@ -25,7 +25,7 @@
     {
       "from_currency": "USD",
       "to_currency": "RUB",
-      "rate": 80.0
+      "rate": "80"
     }
   ]
 }