Revert "webui: fix diff view failing when added file doesn't exist in working directory"

This reverts commit 4c7865b4763552f4294e7a3738b796ea918a7c3d.

The real problem appears to be a race of some kind.
This is not the fix.
diff --git a/webui/src/web-components/sketch-diff2-view.ts b/webui/src/web-components/sketch-diff2-view.ts
index fd42e60..1b673cd 100644
--- a/webui/src/web-components/sketch-diff2-view.ts
+++ b/webui/src/web-components/sketch-diff2-view.ts
@@ -493,15 +493,6 @@
               `Could not get working copy for deleted file ${file.path}, using empty content`,
             );
             this.modifiedCode = "";
-          } else if (file.status === "A" && file.new_hash) {
-            // For added files that don't exist in working directory,
-            // fall back to the committed content
-            console.warn(
-              `Could not get working copy for added file ${file.path}, using committed content`,
-            );
-            this.modifiedCode = await this.gitService.getFileContent(
-              file.new_hash,
-            );
           } else {
             // For any other file status, propagate the error
             console.error(