Set up domain-registry proxy in Crash environment

- Created configs for Proxy server, GKE, and terraform
- Created sans_list file for use with tarsier client
- Updated allowedClients in registry server

TODO: Update dr-bashrc to support crash environment

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=236659249

java/google/registry/proxy/ProxyConfig.java

@@ -29,6 +29,7 @@ public class ProxyConfig {
     SANDBOX,
     SANDBOX_CANARY,
     ALPHA,
+    CRASH,
     LOCAL,
   }