Add comprehensive authentik documentation and improve role configuration

- Add authentik-deployment-guide.md: Complete step-by-step deployment guide
- Add architecture-decisions.md: Document native DB vs containerized rationale
- Add authentication-architecture.md: SSO strategy and integration patterns
- Update deployment-guide.md: Integrate authentik deployment procedures
- Update security-hardening.md: Add multi-layer security documentation
- Update service-integration-guide.md: Add authentik integration examples
- Update README.md: Professional project overview with architecture benefits
- Update authentik role: Fix HTTP binding, add security configs, improve templates
- Remove unused authentik task files: containers.yml, networking.yml

Key improvements:
* Document security benefits of native databases over containers
* Document Unix socket IPC architecture advantages
* Provide comprehensive troubleshooting and deployment procedures
* Add forward auth integration patterns for services
* Fix authentik HTTP binding from 127.0.0.1 to 0.0.0.0
* Add shared memory and IPC security configurations

roles/authentik/templates/authentik-server.container

@@ -11,6 +11,11 @@ EnvironmentFile={{ authentik_home }}/.env
 User={{ authentik_uid }}:{{ authentik_gid }}
 Annotation=run.oci.keep_original_groups=1
 
+# Security configuration for shared memory and IPC
+Volume=/dev/shm:/dev/shm:rw
+SecurityLabelDisable=true
+AddCapability=IPC_OWNER
+
 # Logging configuration
 LogDriver=k8s-file
 LogOpt=path={{ authentik_home }}/logs/server.log