refactor: modularize project structure and separate API from crawlers

- Introduce app/ package with config, services (storage, notifications), API server, and crawler modules
- Add BaseCrawler and BarronsCrawler; extract notifications and storage
- Keep enhanced_crawler.py as back-compat entry delegating to app.runner
- Add template crawler for future sites
- Update README with new structure and usage
- Extend .env.template with DATA_DIR/LOG_DIR options

app/config.py

@@ -0,0 +1,96 @@
+import os
+import logging
+from dataclasses import dataclass
+
+
+@dataclass
+class EmailConfig:
+    smtp_server: str
+    smtp_port: int
+    smtp_security: str  # 'ssl' | 'starttls' | 'none'
+    from_email: str
+    to_email: str
+    username: str
+    password: str
+
+
+@dataclass
+class AppConfig:
+    check_interval: int
+    log_level: str
+    always_notify_on_startup: bool
+    webhook_url: str | None
+    discord_webhook: str | None
+    data_dir: str
+    log_dir: str
+    email: EmailConfig | None
+
+
+def _resolve_dir(env_key: str, default_subdir: str) -> str:
+    # Prefer explicit env var
+    val = os.getenv(env_key)
+    if val:
+        return val
+    # Prefer Docker paths if present
+    docker_path = f"/app/{default_subdir}"
+    if os.path.isdir(docker_path):
+        return docker_path
+    # Fallback to local ./subdir
+    return os.path.join(os.getcwd(), default_subdir)
+
+
+def load_email_config() -> EmailConfig | None:
+    required = [
+        'EMAIL_SMTP_SERVER', 'EMAIL_FROM', 'EMAIL_TO', 'EMAIL_USERNAME', 'EMAIL_PASSWORD'
+    ]
+    if not all(os.getenv(k) for k in required):
+        return None
+
+    security = os.getenv('EMAIL_SMTP_SECURITY', 'starttls').lower()
+    default_port = 465 if security == 'ssl' else 587 if security == 'starttls' else 25
+    smtp_port = int(os.getenv('EMAIL_SMTP_PORT', default_port))
+
+    return EmailConfig(
+        smtp_server=os.getenv('EMAIL_SMTP_SERVER', ''),
+        smtp_port=smtp_port,
+        smtp_security=security,
+        from_email=os.getenv('EMAIL_FROM', ''),
+        to_email=os.getenv('EMAIL_TO', ''),
+        username=os.getenv('EMAIL_USERNAME', ''),
+        password=os.getenv('EMAIL_PASSWORD', ''),
+    )
+
+
+def setup_logging(level: str, log_dir: str) -> logging.Logger:
+    os.makedirs(log_dir, exist_ok=True)
+    logging.basicConfig(
+        level=getattr(logging, level.upper(), logging.INFO),
+        format='%(asctime)s - %(levelname)s - %(message)s',
+        handlers=[
+            logging.FileHandler(os.path.join(log_dir, 'crawler.log')),
+            logging.StreamHandler(),
+        ],
+    )
+    return logging.getLogger(__name__)
+
+
+def load_config() -> AppConfig:
+    check_interval = int(os.getenv('CHECK_INTERVAL', 300))
+    log_level = os.getenv('LOG_LEVEL', 'INFO')
+    always_notify_on_startup = os.getenv('ALWAYS_NOTIFY_ON_STARTUP', 'false').lower() in ('1', 'true', 'yes')
+    webhook_url = os.getenv('WEBHOOK_URL')
+    discord_webhook = os.getenv('DISCORD_WEBHOOK')
+    data_dir = _resolve_dir('DATA_DIR', 'data')
+    log_dir = _resolve_dir('LOG_DIR', 'logs')
+
+    return AppConfig(
+        check_interval=check_interval,
+        log_level=log_level,
+        always_notify_on_startup=always_notify_on_startup,
+        webhook_url=webhook_url,
+        discord_webhook=discord_webhook,
+        data_dir=data_dir,
+        log_dir=log_dir,
+        email=load_email_config(),
+    )
+