Remove the deprecated codex mcp-server command (#42993)

## What changed

Remove the `codex mcp-server` subcommand and the standalone `codex-mcp-server` crate, including its tests, interface documentation, build dependencies, and run recipe.

## Testing

Update the strict configuration test to use `codex exec hello`, preserving coverage for rejecting unknown configuration overrides.

GitOrigin-RevId: 8688b1f41862d7c2073ea2812a257c0087c55d9c

tools/argument-comment-lint/src/lib.rs

@@ -278,11 +278,7 @@ fn is_meaningful_parameter_name(name: &str) -> bool {
 }
 
 fn is_workspace_crate_name(name: &str) -> bool {
-    name.starts_with("codex_")
-        || matches!(
-            name,
-            "app_test_support" | "core_test_support" | "mcp_test_support"
-        )
+    name.starts_with("codex_") || matches!(name, "app_test_support" | "core_test_support")
 }
 
 #[test]