docs: rewrite README with structured overview and quick start guide

Replaces the minimal project description with a comprehensive README
including a component overview table, quick start instructions, common
Ansible operations, and links to detailed documentation. Aligns with
Red Panda Approval™ standards.

ansible/kernos/kernos.service.j2

@@ -0,0 +1,23 @@
+[Unit]
+Description=Kernos MCP Server
+After=network.target
+
+[Service]
+Type=simple
+User={{kernos_user}}
+Group={{kernos_group}}
+WorkingDirectory={{kernos_directory}}
+ExecStart={{kernos_directory}}/.venv/bin/kernos
+EnvironmentFile={{kernos_directory}}/.env
+Restart=on-failure
+RestartSec=5
+
+# Security hardening
+NoNewPrivileges=false
+ProtectSystem=false
+ProtectHome=false
+PrivateTmp=false
+ReadWritePaths=/
+
+[Install]
+WantedBy=multi-user.target