hide —simulate-proof-failures behind compile flag

The `--simulate-proof-failures` cli param is now only available when codex is compile using the `-d:codex_enable_proof_failures` flag.

codex.nimble

@@ -66,7 +66,7 @@ task testContracts, "Build & run Codex Contract tests":
   test "testContracts"
 
 task testIntegration, "Run integration tests":
-  codexTask()
+  buildBinary "codex", params = "-d:chronicles_runtime_filtering -d:chronicles_log_level=TRACE -d:codex_enable_proof_failures=true"
   test "testIntegration"
 
 task test, "Run tests":

codex/conf.nim

@@ -37,6 +37,7 @@ export DefaultCacheSizeMiB, net, DefaultQuotaBytes, DefaultBlockTtl, DefaultBloc
 
 const
   codex_enable_api_debug_peers* {.booldefine.} = false
+  codex_enable_proof_failures* {.booldefine.} = false
 
 type
   StartUpCommand* {.pure.} = enum
@@ -244,6 +245,7 @@ type
           desc: "Simulates proof failures once every N proofs. 0 = disabled."
           defaultValue: 0
           name: "simulate-proof-failures"
+          hidden
         .}: uint
 
     of initNode: