cob: Rename default history type

Signed-off-by: Alexis Sellier <alexis@radicle.xyz>

radicle-cob/src/backend/git/change.rs

@@ -201,7 +201,7 @@ fn load_contents(
     manifest: &store::Manifest,
 ) -> Result<entry::Contents, error::Load> {
     Ok(match manifest.history_type {
-        HistoryType::Default | HistoryType::Automerge => {
+        HistoryType::Radicle | HistoryType::Automerge => {
             let contents_tree_entry = tree
                 .get_name(CHANGE_BLOB_NAME)
                 .ok_or_else(|| error::Load::NoChange(tree.id().into()))?;

radicle-cob/src/history.rs

@@ -22,7 +22,7 @@ pub use entry::{Contents, Entry, EntryId};
 #[serde(rename_all = "lowercase")]
 pub enum HistoryType {
     #[default]
-    Default,
+    Radicle,
     Automerge,
 }