Clarify interactive install prompt source (#1523)

* fix(use): clarify interactive install prompt source

* chore: add changeset for prompt clarification

Author: Schniz

.changeset/fair-carrots-greet.md

@@ -0,0 +1,5 @@
+---
+"fnm": patch
+---
+
+Clarify the interactive `fnm use` missing-version prompt by prefixing the message with `fnm` so it is obvious which tool is asking to install Node.

src/commands/use.rs

@@ -181,7 +181,7 @@ fn should_install_interactively(requested_version: &UserVersion) -> bool {
     }
 
     let error_message = format!(
-        "Can't find an installed Node version matching {}.",
+        "fnm can't find an installed Node version matching {}.",
         requested_version.to_string().italic()
     );
     eprintln!("{}", error_message.red());