revert: restore lora_config.json - file deletion had no effect

Analysis confirms: both model loading errors and test failures are IDENTICAL with/without this file. The file is not the root cause.

lora_config.json

@@ -0,0 +1 @@
+{"rank": 16, "alpha": 32, "dropout": 0.1, "target_modules": ["attention.self.query", "attention.self.value", "attention.output.dense", "intermediate.dense", "output.dense"]}