[codex] Fix Windows BuildBuddy Bazel wrapper execution (#25915)

## Why

#25156 moved Bazel CI launches into a shared Python wrapper. On Windows,
launching Bazel with `os.execvp` can split the spaced
`--test_env=PATH=...` argument and fail to propagate the eventual Bazel
exit status, allowing jobs to pass without running tests. This reapplies
the wrapper after #25909 with a Windows-safe launch path.

## What changed

Use a waited `subprocess.run` launch on Windows while preserving
`os.execvp` on Unix. Add a process-level regression test for spaced
arguments and child exit status, and run it on Windows Bazel shard 1.

## Experiment

To confirm Bazel was actually invoking tests, patch `87b61d0be6`
temporarily added an intentionally failing `codex-core` unit test. Bazel
failed on that sentinel on all three major platforms:

- [Linux Bazel
test](https://github.com/openai/codex/actions/runs/26841132773/job/79151062486)
- [macOS Bazel
test](https://github.com/openai/codex/actions/runs/26841132773/job/79151062362)
- [Windows Bazel test shard
1/4](https://github.com/openai/codex/actions/runs/26841132773/job/79151062155)

The sentinel was removed after collecting this evidence. Windows Bazel
[clippy](https://github.com/openai/codex/actions/runs/26841132773/job/79151062914)
and [release
verification](https://github.com/openai/codex/actions/runs/26841132773/job/79151062739)
also passed.

## Validation

After removing the sentinel, `just test -p codex-core` no longer
reported it. The local run retained two unrelated environment-specific
failures.

.github/scripts/run-bazel-query-ci.sh

@@ -2,48 +2,17 @@
 
 set -euo pipefail
 
-# Run Bazel queries with the same CI startup settings as the main build/test
-# invocation so target-discovery queries can reuse the same Bazel server.
+# Run target-discovery queries with the same startup settings as the main
+# build/test invocation so they can reuse the same Bazel server. Queries only
+# enumerate labels, so they intentionally do not select CI or remote configs.
 
-query_args=()
-windows_cross_compile=0
-while [[ $# -gt 0 ]]; do
-  case "$1" in
-    --windows-cross-compile)
-      windows_cross_compile=1
-      shift
-      ;;
-    --)
-      shift
-      break
-      ;;
-    *)
-      query_args+=("$1")
-      shift
-      ;;
-  esac
-done
-
-if [[ $# -ne 1 ]]; then
-  echo "Usage: $0 [--windows-cross-compile] [<bazel query args>...] -- <query expression>" >&2
+if [[ $# -lt 2 || "${@: -2:1}" != "--" ]]; then
+  echo "Usage: $0 [<bazel query args>...] -- <query expression>" >&2
   exit 1
 fi
 
-query_expression="$1"
-
-ci_config=ci-linux
-case "${RUNNER_OS:-}" in
-  macOS)
-    ci_config=ci-macos
-    ;;
-  Windows)
-    if [[ $windows_cross_compile -eq 1 ]]; then
-      ci_config=ci-windows-cross
-    else
-      ci_config=ci-windows
-    fi
-    ;;
-esac
+query_args=("${@:1:$#-2}")
+query_expression="${@: -1}"
 
 bazel_startup_args=()
 if [[ -n "${BAZEL_OUTPUT_USER_ROOT:-}" ]]; then
@@ -60,12 +29,6 @@ run_bazel() {
 }
 
 bazel_query_args=(--noexperimental_remote_repo_contents_cache query)
-if [[ -n "${BUILDBUDDY_API_KEY:-}" ]]; then
-  bazel_query_args+=(
-    "--config=${ci_config}"
-    "--remote_header=x-buildbuddy-api-key=${BUILDBUDDY_API_KEY}"
-  )
-fi
 
 if [[ -n "${BAZEL_REPO_CONTENTS_CACHE:-}" ]]; then
   bazel_query_args+=("--repo_contents_cache=${BAZEL_REPO_CONTENTS_CACHE}")
@@ -75,7 +38,10 @@ if [[ -n "${BAZEL_REPOSITORY_CACHE:-}" ]]; then
   bazel_query_args+=("--repository_cache=${BAZEL_REPOSITORY_CACHE}")
 fi
 
-bazel_query_args+=("${query_args[@]}" "$query_expression")
+if (( ${#query_args[@]} > 0 )); then
+  bazel_query_args+=("${query_args[@]}")
+fi
+bazel_query_args+=("$query_expression")
 
 if (( ${#bazel_startup_args[@]} > 0 )); then
   run_bazel "${bazel_startup_args[@]}" "${bazel_query_args[@]}"