T6: Decompose CLI — main.py → 9 command files, config.py → config_cmd.py

Split infrastructure/cli/:
- main.py (330 LOC) → 9 files in infrastructure/cli/commands/:
  * init.py, forecast.py, scenario.py, whatif.py, compare.py
  * import_xlsx.py, export_xlsx.py, analyze.py, info.py
- config.py (428 LOC) → commands/config_cmd.py (15 sub-commands)
- main.py → app.py (entry point: registers all commands)
- New: paths.py (MODEL_PATH, DATA_DIR)
- New: services.py (composition root + helpers: load_model, save_model,
  build_services, resolve_currency, convert_value, fmt_amount)
- cli/__init__.py (empty) удалён

Each command module: <100 LOC.
pyproject.toml: cf = infrastructure.cli.app:app
tests/test_cli.py: import обновлён на infrastructure.cli.app

CLI behavior идентично, все команды работают.
Tests: 67/67 pass.

infrastructure/cli/services.py

@@ -0,0 +1,60 @@
+"""Composition root + общие хелперы для CLI-команд."""
+from __future__ import annotations
+
+from decimal import Decimal
+
+from rich.console import Console
+
+from application.forecast import ForecastService
+from application.scenarios import ScenarioService
+from domain import CurrencyConverter, FinancialModel
+from infrastructure.ai.assistant import AssistantService
+from infrastructure.cli.paths import MODEL_PATH
+from infrastructure.repositories import JsonFileRepository
+
+
+console = Console()
+
+_json_repo = JsonFileRepository()
+
+
+def load_model() -> FinancialModel:
+    if MODEL_PATH.exists():
+        return _json_repo.load(MODEL_PATH)
+    return FinancialModel()
+
+
+def save_model(model: FinancialModel) -> None:
+    _json_repo.save(model, MODEL_PATH)
+
+
+def build_services(model: FinancialModel) -> tuple[ForecastService, ScenarioService, AssistantService, CurrencyConverter]:
+    """Composition root: собрать граф сервисов с зависимостями."""
+    converter = CurrencyConverter(model.exchange_rates)
+    forecast_service = ForecastService(model)
+    scenario_service = ScenarioService(model)
+    assistant_service = AssistantService(
+        model, forecast_service=forecast_service, converter=converter
+    )
+    return forecast_service, scenario_service, assistant_service, converter
+
+
+def resolve_currency(model: FinancialModel, currency: str | None) -> tuple[str, str]:
+    target = currency or model.base_currency
+    converter = CurrencyConverter(model.exchange_rates)
+    symbol = converter.get_symbol(target)
+    return target, symbol
+
+
+def convert_value(
+    converter: CurrencyConverter, amount: Decimal, from_curr: str, to_curr: str
+) -> Decimal:
+    if to_curr == from_curr:
+        return amount
+    return converter.convert(amount, from_curr, to_curr)
+
+
+def fmt_amount(amount: Decimal | float, currency: str, symbol: str) -> str:
+    if isinstance(amount, Decimal):
+        return f"{symbol}{amount:,.2f}"
+    return f"{symbol}{amount:,.2f}"