feat: enhance security with improved password hashing and logging

- Add Argon2PasswordHasher with high security settings as primary hasher
- Implement fallback to PBKDF2PasswordHasher for CentOS 7/Python 3.6 compatibility
- Add argon2-cffi dependency to requirements.txt
- Replace all print statements with proper logging calls across codebase
- Implement comprehensive logging configuration with multiple handlers:
  * ivatar.log - General application logs (INFO level)
  * ivatar_debug.log - Detailed debug logs (DEBUG level)
  * security.log - Security events (WARNING level)
- Add configurable LOGS_DIR setting with local config override support
- Create config_local.py.example with logging configuration examples
- Fix code quality issues (flake8, black formatting, import conflicts)
- Maintain backward compatibility with existing password hashes

Security improvements:
- New passwords use Argon2 (memory-hard, ASIC-resistant)
- Enhanced PBKDF2 iterations for fallback scenarios
- Structured logging for security monitoring and debugging
- Production-ready configuration with flexible log locations

Tests: 85/113 passing (failures due to external DNS/API dependencies)
Code quality: All pre-commit hooks passing

create.sh

@@ -2,11 +2,11 @@
 
 oc new-project ivatar
 
-DB_PASSWORD=`openssl rand -base64 16`
-DB_ROOT_PASSWORD=`openssl rand -base64 16`
+DB_PASSWORD=$(openssl rand -base64 16)
+DB_ROOT_PASSWORD=$(openssl rand -base64 16)
 
 if [ -n "$USE_MYSQL" ]; then
-  DB_CMDLINE="mysql-persistent
+    DB_CMDLINE="mysql-persistent
   --group=python+mysql-persistent
   -e MYSQL_USER=ivatar
   -p MYSQL_USER=ivatar
@@ -17,7 +17,7 @@ if [ -n "$USE_MYSQL" ]; then
   -e MYSQL_ROOT_PASSWORD=$DB_ROOT_PASSWORD
   -p MYSQL_ROOT_PASSWORD=$DB_ROOT_PASSWORD"
 else
-  DB_CMDLINE="postgresql-persistent
+    DB_CMDLINE="postgresql-persistent
   -e POSTGRESQL_USER=ivatar
   -p POSTGRESQL_USER=ivatar
   -e POSTGRESQL_DATABASE=ivatar
@@ -35,8 +35,8 @@ if [ -n "$LKERNAT_GITLAB_OPENSHIFT_ACCESS_TOKEN" ]; then
 fi
 
 oc new-app $SECRET_CMDLINE python~https://git.linux-kernel.at/oliver/ivatar.git \
-  -e IVATAR_MAILGUN_API_KEY=$IVATAR_MAILGUN_API_KEY \
-  -e IVATAR_MAILGUN_SENDER_DOMAIN=$IVATAR_MAILGUN_SENDER_DOMAIN \
-  $DB_CMDLINE
+    -e IVATAR_MAILGUN_API_KEY=$IVATAR_MAILGUN_API_KEY \
+    -e IVATAR_MAILGUN_SENDER_DOMAIN=$IVATAR_MAILGUN_SENDER_DOMAIN \
+    $DB_CMDLINE
 
 oc expose svc/ivatar