feat: Add protocol_specific_addresses.json file

This way we can define protocol and chain specific addresses in this file and use them in the Encoders

--- don't change below this line ---
ENG-4306 Took 1 hour 4 minutes

config/protocol_specific_addresses.json

@@ -0,0 +1,11 @@
+{
+  "ethereum": {
+    "vm:balancer_v2": {
+      "vault_address": "0xba12222222228d8ba445958a75a0704d566bf2c8"
+    },
+    "vm:curve": {
+      "native_token_address": "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE",
+      "meta_registry_address": "0xF98B45FA17DE75FB1aD0e7aFD971b0ca00e379fC"
+    }
+  }
+}