Add builder-ish methods to InstanceSnapshot to make middleware code more readable

src/snapshot_middleware/txt.rs

@@ -1,4 +1,4 @@
-use std::{borrow::Cow, str};
+use std::str;
 
 use maplit::hashmap;
 use rbx_dom_weak::{RbxId, RbxTree, RbxValue};
@@ -48,18 +48,15 @@ impl SnapshotMiddleware for SnapshotTxt {
             .path()
             .with_file_name(format!("{}.meta.json", instance_name));
 
-        let mut snapshot = InstanceSnapshot {
-            snapshot_id: None,
-            metadata: InstanceMetadata {
+        let mut snapshot = InstanceSnapshot::new()
+            .name(instance_name)
+            .class_name("StringValue")
+            .properties(properties)
+            .metadata(InstanceMetadata {
                 instigating_source: Some(entry.path().to_path_buf().into()),
                 relevant_paths: vec![entry.path().to_path_buf(), meta_path.clone()],
                 ..Default::default()
-            },
-            name: Cow::Owned(instance_name.to_owned()),
-            class_name: Cow::Borrowed("StringValue"),
-            properties,
-            children: Vec::new(),
-        };
+            });
 
         if let Some(meta_entry) = vfs.get(meta_path).with_not_found()? {
             let meta_contents = meta_entry.contents(vfs)?;