Update Rust edition to 2024

LilyFirefly · LilyFirefly · commit 0920c90e2199 · 2025-08-01T09:36:04.000+01:00
diff --git a/Cargo.toml b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "rustfluent"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [lib]
