fix(monitoring): escape shell vars in glances command

Compose ate ${GLANCES_OPT}/${PYTHON_VERSION} in the command string
(empty), leaving bare 'glances' → TUI mode vs curses crash.

monitoring/compose.yaml

@@ -66,7 +66,8 @@ services:
     command:
       - "/bin/sh"
       - "-c"
-      - "/venv/bin/python${PYTHON_VERSION} -m glances ${GLANCES_OPT}"
+      # $$ zodat compose niet interpoleert; shell doet dit runtime
+      - "/venv/bin/python$${PYTHON_VERSION} -m glances $${GLANCES_OPT}"
     container_name: "glances"
     environment:
       - "GLANCES_OPT=-w -C /config/glances.conf"