chore: update codetracer-trace-format submodule branch to main

The remote master branch has been deleted; main is now the default.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: zah

.gitmodules

@@ -87,4 +87,4 @@
 [submodule "libs/codetracer-trace-format"]
 	path = libs/codetracer-trace-format
 	url = https://github.com/metacraft-labs/codetracer-trace-format.git
-	branch = master
+	branch = main