feat: Add email logging and monitoring system

- Add EmailLog model to database.py for tracking sent emails
- Modify email_service.py to log all sent emails to database
- Track email type (welcome, password_reset, notification)
- Record sender, recipient, subject, status, timestamps
- Supports monitoring email delivery success/failure

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

database.py

@@ -2525,6 +2525,54 @@ class PopularPagesDaily(Base):
         return f"<PopularPagesDaily {self.date} {self.path}>"
 
 
+# ============================================================
+# EMAIL LOGGING
+# ============================================================
+
+class EmailLog(Base):
+    """
+    Log wszystkich wysłanych emaili systemowych.
+
+    Śledzi:
+    - Emaile rejestracyjne (weryfikacja)
+    - Emaile resetowania hasła
+    - Powiadomienia systemowe
+    - Status dostarczenia
+
+    Created: 2026-01-14
+    """
+    __tablename__ = 'email_logs'
+
+    id = Column(Integer, primary_key=True)
+
+    # Dane emaila
+    email_type = Column(String(50), nullable=False, index=True)  # welcome, password_reset, notification
+    recipient_email = Column(String(255), nullable=False, index=True)
+    recipient_name = Column(String(255), nullable=True)
+    subject = Column(String(500), nullable=False)
+
+    # Powiązanie z użytkownikiem (opcjonalne)
+    user_id = Column(Integer, ForeignKey('users.id', ondelete='SET NULL'), nullable=True)
+
+    # Status
+    status = Column(String(20), default='pending', index=True)  # pending, sent, failed
+    error_message = Column(Text, nullable=True)
+
+    # Metadane
+    sender_email = Column(String(255), nullable=True)
+    ip_address = Column(String(45), nullable=True)  # IP requestu (jeśli dostępne)
+
+    # Timestamps
+    created_at = Column(DateTime, default=datetime.utcnow)
+    sent_at = Column(DateTime, nullable=True)
+
+    # Relacje
+    user = relationship('User', backref='email_logs')
+
+    def __repr__(self):
+        return f"<EmailLog {self.id} {self.email_type} -> {self.recipient_email} ({self.status})>"
+
+
 # ============================================================
 # DATABASE INITIALIZATION
 # ============================================================

email_service.py

@@ -204,7 +204,10 @@ def send_email(
     subject: str,
     body_text: str,
     body_html: Optional[str] = None,
-    from_address: Optional[str] = None
+    from_address: Optional[str] = None,
+    email_type: str = 'notification',
+    user_id: Optional[int] = None,
+    recipient_name: Optional[str] = None
 ) -> bool:
     """
     Send email using the global Email Service instance
@@ -215,6 +218,9 @@ def send_email(
         body_text: Plain text email body
         body_html: HTML email body (optional)
         from_address: Sender email (optional)
+        email_type: Type of email for logging (welcome, password_reset, notification)
+        user_id: User ID for logging (optional)
+        recipient_name: Recipient name for logging (optional)
 
     Returns:
         True if sent successfully, False otherwise
@@ -227,7 +233,74 @@ def send_email(
     if isinstance(to, str):
         to = [to]
 
-    return _email_service.send_mail(to, subject, body_text, body_html, from_address)
+    result = _email_service.send_mail(to, subject, body_text, body_html, from_address)
+
+    # Log email to database
+    _log_email(
+        email_type=email_type,
+        recipient_emails=to,
+        recipient_name=recipient_name,
+        subject=subject,
+        user_id=user_id,
+        sender_email=from_address or _email_service.mail_from if _email_service else None,
+        success=result
+    )
+
+    return result
+
+
+def _log_email(
+    email_type: str,
+    recipient_emails: List[str],
+    subject: str,
+    success: bool,
+    recipient_name: Optional[str] = None,
+    user_id: Optional[int] = None,
+    sender_email: Optional[str] = None,
+    error_message: Optional[str] = None
+) -> None:
+    """
+    Log email to database for monitoring.
+
+    Args:
+        email_type: Type of email (welcome, password_reset, notification)
+        recipient_emails: List of recipient email addresses
+        subject: Email subject
+        success: Whether email was sent successfully
+        recipient_name: Recipient name (optional)
+        user_id: User ID (optional)
+        sender_email: Sender email address (optional)
+        error_message: Error message if failed (optional)
+    """
+    try:
+        from database import SessionLocal, EmailLog
+        from datetime import datetime
+
+        db = SessionLocal()
+        try:
+            for email in recipient_emails:
+                log_entry = EmailLog(
+                    email_type=email_type,
+                    recipient_email=email,
+                    recipient_name=recipient_name,
+                    subject=subject,
+                    user_id=user_id,
+                    sender_email=sender_email,
+                    status='sent' if success else 'failed',
+                    sent_at=datetime.utcnow() if success else None,
+                    error_message=error_message if not success else None
+                )
+                db.add(log_entry)
+            db.commit()
+            logger.info(f"Email logged: {email_type} -> {recipient_emails} (status: {'sent' if success else 'failed'})")
+        except Exception as e:
+            db.rollback()
+            logger.error(f"Failed to log email to database: {e}")
+        finally:
+            db.close()
+    except ImportError:
+        # Database not available (e.g., during testing)
+        logger.warning("Could not log email - database module not available")
 
 
 def is_configured() -> bool:
@@ -325,7 +398,13 @@ https://nordabiznes.pl
 </html>
 """
 
-    return send_email([email], subject, body_text, body_html)
+    return send_email(
+        to=[email],
+        subject=subject,
+        body_text=body_text,
+        body_html=body_html,
+        email_type='password_reset'
+    )
 
 
 def send_welcome_email(email: str, name: str, verification_url: str) -> bool:
@@ -417,4 +496,11 @@ https://nordabiznes.pl
 </html>
 """
 
-    return send_email([email], subject, body_text, body_html)
+    return send_email(
+        to=[email],
+        subject=subject,
+        body_text=body_text,
+        body_html=body_html,
+        email_type='welcome',
+        recipient_name=name
+    )