many improvements

src/error.rs

@@ -1,8 +1,13 @@
-use enostr;
-
-#[derive(Eq, PartialEq)]
+#[derive(Eq, PartialEq, Debug)]
 pub enum Error {
     Nostr(enostr::Error),
+    Generic(String),
+}
+
+impl From<String> for Error {
+    fn from(s: String) -> Self {
+        Error::Generic(s)
+    }
 }
 
 impl From<enostr::Error> for Error {