feat: Add admin notifications when user accepts/rejects changes

- Create notification for all admins when user accepts proposed changes
- Create notification for all admins when user rejects proposed changes
- Clear proposed_changes fields after user decision
- Include rejection reason in admin notification

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

blueprints/membership/routes.py

@@ -12,7 +12,7 @@ from flask import render_template, request, redirect, url_for, flash, jsonify
 from flask_login import login_required, current_user
 
 from . import bp
-from database import SessionLocal, MembershipApplication, CompanyDataRequest, Company
+from database import SessionLocal, MembershipApplication, CompanyDataRequest, Company, UserNotification, User
 
 logger = logging.getLogger(__name__)
 
@@ -336,6 +336,25 @@ def accept_changes(app_id):
         application.status = 'under_review'
         application.updated_at = datetime.now()
 
+        # Clear proposed changes (they've been applied)
+        application.proposed_changes = None
+        application.proposed_changes_at = None
+        application.proposed_changes_comment = None
+
+        # Create notification for admins
+        admins = db.query(User).filter(User.is_admin == True).all()
+        for admin in admins:
+            notification = UserNotification(
+                user_id=admin.id,
+                title='Użytkownik zaakceptował zmiany',
+                message=f'Użytkownik {current_user.name or current_user.email} zaakceptował proponowane zmiany dla firmy "{application.company_name}". Deklaracja oczekuje na ostateczne zatwierdzenie.',
+                notification_type='alert',
+                related_type='membership_application',
+                related_id=app_id,
+                action_url=f'/admin/membership/{app_id}'
+            )
+            db.add(notification)
+
         db.commit()
 
         logger.info(
@@ -386,6 +405,7 @@ def reject_changes(app_id):
         application.proposed_changes = None
         application.proposed_changes_at = None
         application.proposed_changes_by_id = None
+        application.proposed_changes_comment = None
 
         # Add user's rejection reason to review_comment
         if user_comment:
@@ -396,6 +416,20 @@ def reject_changes(app_id):
         application.status = 'under_review'
         application.updated_at = datetime.now()
 
+        # Create notification for admins
+        admins = db.query(User).filter(User.is_admin == True).all()
+        for admin in admins:
+            notification = UserNotification(
+                user_id=admin.id,
+                title='Użytkownik odrzucił zmiany',
+                message=f'Użytkownik {current_user.name or current_user.email} odrzucił proponowane zmiany dla firmy "{application.company_name}".{" Powód: " + user_comment if user_comment else ""} Deklaracja wraca do rozpatrzenia z oryginalnymi danymi.',
+                notification_type='alert',
+                related_type='membership_application',
+                related_id=app_id,
+                action_url=f'/admin/membership/{app_id}'
+            )
+            db.add(notification)
+
         db.commit()
 
         logger.info(