Patch to make it easy to sed in the configured python interpeter and mention the liquidctl use flag in the error message.

--- a/coolercontrold/daemon/src/repositories/liquidctl/liqctld_service.rs
+++ b/coolercontrold/daemon/src/repositories/liquidctl/liqctld_service.rs
@@ -122,7 +122,7 @@ fn create_command() -> (String, &'static str) {
         info!("Running liqctld inside an AppImage");
         (format!("{appdir}/usr/bin/python3"), "-I")
     } else {
-        ("python3".to_string(), "-q")
+        ("@@PYTHON@@".to_string(), "-q")
     }
 }
 
--- a/coolercontrold/daemon/src/repositories/liquidctl/liquidctl_repo.rs
+++ b/coolercontrold/daemon/src/repositories/liquidctl/liquidctl_repo.rs
@@ -82,10 +82,10 @@ impl LiquidctlRepo {
         }
         if let Err(err) = liqctld_service::verify_env().await {
             let msg = format!(
-                "Python liquidctl system package not detected. If you want liquidctl device \
-                support, please make sure the liquidctl package is installed with your \
-                distribution's package manager. If not, you may disable liquidctl support \
-                to no longer see this message. {err}"
+                "Python liquidctl system package not detected or liquidctl use flag is disabled \
+                for coolercontrold. If you want liquidctl device support, please make sure \
+                the liquidctl use flag is enabled for coolercontrold. If not, you may disable \
+                liquidctl support to no longer see this message. {err}"
             );
             return Err(InitError::PythonEnv { msg }.into());
         }