feat: use edition 2024 by default in new projects (#329)

Author: seqre

cot-cli/src/project_template/Cargo.toml.template

@@ -1,7 +1,7 @@
 [package]
 name = "{{ project_name }}"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 [dependencies]
 askama = "0.14"