[codex] Revert shared BuildBuddy Bazel wrapper (#25909)

## Why

PR #25905 intentionally adds a failing `codex-core` unit test, but its
[Bazel test on Windows
check](https://github.com/openai/codex/actions/runs/26837526950/job/79135369259)
passed. That shows the Bazel configuration introduced by #25156 is not
behaving as expected, so revert it while the configuration can be
investigated separately.

## What changed

Revert #25156 in full, restoring the previous Bazel remote
configuration, CI scripts, workflows, `rusty_v8` handling, and
documentation. This removes the shared BuildBuddy wrapper and its tests.

## Validation

Not run locally; this exact revert was prioritized for a fast rollback.

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

@@ -2,17 +2,48 @@
 
 set -euo pipefail
 
-# 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.
+# 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.
 
-if [[ $# -lt 2 || "${@: -2:1}" != "--" ]]; then
-  echo "Usage: $0 [<bazel query args>...] -- <query expression>" >&2
+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
   exit 1
 fi
 
-query_args=("${@:1:$#-2}")
-query_expression="${@: -1}"
+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
 
 bazel_startup_args=()
 if [[ -n "${BAZEL_OUTPUT_USER_ROOT:-}" ]]; then
@@ -29,6 +60,12 @@ 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}")
@@ -38,10 +75,7 @@ if [[ -n "${BAZEL_REPOSITORY_CACHE:-}" ]]; then
   bazel_query_args+=("--repository_cache=${BAZEL_REPOSITORY_CACHE}")
 fi
 
-if (( ${#query_args[@]} > 0 )); then
-  bazel_query_args+=("${query_args[@]}")
-fi
-bazel_query_args+=("$query_expression")
+bazel_query_args+=("${query_args[@]}" "$query_expression")
 
 if (( ${#bazel_startup_args[@]} > 0 )); then
   run_bazel "${bazel_startup_args[@]}" "${bazel_query_args[@]}"