use deep clone instead of reference copy

- Original code creates a reference copy of `$doc` into `$work` which means that editing values of `$work` changes the values in `$doc`.
- Fix this behaviour by creating a deep clone of `$doc` into `$work`, so underlying values aren't cross-referenced.

src/lib/helpers/object.ts

@@ -36,3 +36,14 @@ export function deepEqual<T>(obj1: T, obj2: T): boolean {
 
     return true;
 }
+
+/**
+ * Creates a deep clone of the given object. This function uses the JSON methods for cloning,
+ * so it may not be suitable for objects with functions, symbols, or other non-JSON-safe data.
+ *
+ * @param obj the object to be cloned
+ * @returns a deep clone of the provided object
+ */
+export function deepClone<T>(obj: T): T {
+    return JSON.parse(JSON.stringify(obj));
+}

src/routes/console/project-[project]/databases/database-[database]/collection-[collection]/document-[document]/data/+page.svelte

@@ -15,6 +15,7 @@
     import AttributeItem from '../attributeItem.svelte';
     import { symmetricDifference } from '$lib/helpers/array';
     import { isRelationship, isRelationshipToMany } from '../attributes/store';
+    import { deepClone } from '$lib/helpers/object';
 
     const databaseId = $page.params.database;
     const collectionId = $page.params.collection;
@@ -22,21 +23,23 @@
     const editing = true;
 
     const work = writable(
-        Object.keys($doc)
-            .filter((key) => {
-                return ![
-                    '$id',
-                    '$collection',
-                    '$collectionId',
-                    '$databaseId',
-                    '$createdAt',
-                    '$updatedAt'
-                ].includes(key);
-            })
-            .reduce((obj, key) => {
-                obj[key] = $doc[key];
-                return obj;
-            }, {}) as Models.Document
+        deepClone(
+            Object.keys($doc)
+                .filter((key) => {
+                    return ![
+                        '$id',
+                        '$collection',
+                        '$collectionId',
+                        '$databaseId',
+                        '$createdAt',
+                        '$updatedAt'
+                    ].includes(key);
+                })
+                .reduce((obj, key) => {
+                    obj[key] = $doc[key];
+                    return obj;
+                }, {}) as Models.Document
+        )
     );
 
     async function updateData() {