feat: implement display trait for Ident (#1049)

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Co-authored-by: ZENOTME <st810918843@gmail.com>

Author: ZENOTME

crates/iceberg/src/catalog/mod.rs

@@ -18,7 +18,7 @@
 //! Catalog API for Apache Iceberg
 
 use std::collections::HashMap;
-use std::fmt::Debug;
+use std::fmt::{Debug, Display};
 use std::mem::take;
 use std::ops::Deref;
 
@@ -192,6 +192,12 @@ impl Namespace {
     }
 }
 
+impl Display for NamespaceIdent {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0.join("."))
+    }
+}
+
 /// TableIdent represents the identifier of a table in the catalog.
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Hash)]
 pub struct TableIdent {
@@ -232,6 +238,12 @@ impl TableIdent {
     }
 }
 
+impl Display for TableIdent {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}.{}", self.namespace, self.name)
+    }
+}
+
 /// TableCreation represents the creation of a table in the catalog.
 #[derive(Debug, TypedBuilder)]
 pub struct TableCreation {