feat: document user management system and RBAC implementation

- Update copilot-instructions.md with user model, API routes, and frontend patterns
- Update README.md with RBAC details, user management API, and security sections
- Add user management technical documentation to TECH-CHANGELOG.md
- Bump version to 2025.1.0-alpha.13 with user management changelog entries

server/wsgi.py

@@ -9,6 +9,7 @@ from server.routes.academic_periods import academic_periods_bp
 from server.routes.groups import groups_bp
 from server.routes.clients import clients_bp
 from server.routes.auth import auth_bp
+from server.routes.users import users_bp
 from server.routes.system_settings import system_settings_bp
 from server.database import Session, engine
 from flask import Flask, jsonify, send_from_directory, request
@@ -43,6 +44,7 @@ else:
 # Blueprints importieren und registrieren
 
 app.register_blueprint(auth_bp)
+app.register_blueprint(users_bp)
 app.register_blueprint(clients_bp)
 app.register_blueprint(groups_bp)
 app.register_blueprint(events_bp)