Update dependency textual to v3

Author: renovate[bot]

monitor/requirements.txt

@@ -26,7 +26,7 @@ propcache==0.3.0
 Pygments==2.19.1
 rich==13.9.4
 sniffio==1.3.1
-textual==2.1.2
+textual==3.0.0
 textual-dev==1.7.0
 textual-serve==1.1.1
 typing_extensions==4.12.2