heap alloc flakeref in TypeUnsupported errors

wire/lib/src/errors.rs

···
         url("{DOCS_URL}#{}", self.code().unwrap())
     )]
     #[error("The flakref had an unsupported type: {:#?}", .0)]
-    TypeUnsupported(FlakeRef),
+    TypeUnsupported(Box<FlakeRef>),
 }
 
 #[derive(Debug, Diagnostic, Error)]

wire/lib/src/hive/mod.rs

···
             | FlakeRef::SourceHut { .. },
         ) => Ok(HiveLocation::Flake(path)),
         Err(err) => Err(HiveLocationError::Malformed(err)),
-        Ok(flakeref) => Err(HiveLocationError::TypeUnsupported(flakeref)),
+        Ok(flakeref) => Err(HiveLocationError::TypeUnsupported(Box::new(flakeref))),
     }
 }