feat(cli): dynamic default range, --version, --verbose, --debug, --url, --api-key, --config

- #17: default date range falls back to current month when .env dates are missing
- #18: add --version, --verbose, --debug flags
- #20: add --url, --api-key, --config CLI overrides
- Config supports CLI overrides for URL/API key and explicit config file loading
- Update README with new CLI options
- Add tests for new flags and config overrides

Closes #17, closes #18, closes #20

redmine_reporter/config.py

@@ -1,4 +1,5 @@
 import os
+from datetime import date, timedelta
 from typing import Union
 
 from dotenv import load_dotenv
@@ -11,12 +12,32 @@ TRUE_VALUES = {"1", "true", "yes", "on"}
 
 
 class Config:
+    _cli_url: str | None = None
+    _cli_api_key: str | None = None
+
+    @classmethod
+    def load_config(cls, path: str) -> None:
+        """Загружает переменные из указанного .env-файла с override."""
+        load_dotenv(path, override=True)
+
+    @classmethod
+    def set_redmine_url(cls, url: str) -> None:
+        cls._cli_url = url.strip().rstrip("/") if url else None
+
+    @classmethod
+    def set_redmine_api_key(cls, key: str) -> None:
+        cls._cli_api_key = key.strip() if key else None
+
     @classmethod
     def get_redmine_url(cls) -> str:
+        if cls._cli_url is not None:
+            return cls._cli_url
         return os.getenv("REDMINE_URL", "").strip().rstrip("/")
 
     @classmethod
     def get_redmine_api_key(cls) -> str:
+        if cls._cli_api_key is not None:
+            return cls._cli_api_key
         return os.getenv("REDMINE_API_KEY", "").strip()
 
     @classmethod
@@ -53,8 +74,17 @@ class Config:
         default_to_date = os.getenv("DEFAULT_TO_DATE", "").strip()
         if default_from_date and default_to_date:
             return f"{default_from_date}--{default_to_date}"
-        # fallback hardcoded
-        return "2025-12-19--2026-01-31"
+
+        # fallback: текущий месяц
+        today = date.today()
+        start = today.replace(day=1)
+        # последний день месяца: берём первое число следующего месяца и вычитаем день
+        if today.month == 12:
+            next_month = today.replace(year=today.year + 1, month=1, day=1)
+        else:
+            next_month = today.replace(month=today.month + 1, day=1)
+        end = next_month - timedelta(days=1)
+        return f"{start.isoformat()}--{end.isoformat()}"
 
     @classmethod
     def validate(cls) -> None: