Add some performance traces for blob-merges

Author: Byron

gix-merge/src/blob/platform/merge.rs

@@ -376,6 +376,10 @@ impl<'parent> PlatformRef<'parent> {
         labels: builtin_driver::text::Labels<'_>,
         context: gix_command::Context,
     ) -> Result<(inner::builtin_merge::Pick, Resolution), Error> {
+        let _span = gix_trace::coarse!(
+            "gix_merge::blob::PlatformRef::merge()",
+            current_rela_path = %self.current.rela_path
+        );
         match self.configured_driver() {
             Ok(driver) => {
                 let mut cmd = self.prepare_external_driver(driver.command.clone(), labels, context)?;

gix-merge/src/blob/platform/set_resource.rs

@@ -46,6 +46,7 @@ impl Platform {
         kind: ResourceKind,
         objects: &impl gix_object::FindObjectOrHeader,
     ) -> Result<(), Error> {
+        gix_trace::detail!("gix_merge::blob::Platform::set_resource()", %id, %rela_path);
         if !matches!(
             mode,
             gix_object::tree::EntryKind::Blob | gix_object::tree::EntryKind::BlobExecutable