bazel: re-organize bazelrc (#15522)

Replaced ci.bazelrc and v8-ci.bazelrc by custom configs inside the main
.bazelrc file. As a result, github workflows setup is simplified down to
a single '--config=<foo>' flag usage.

Moved the build metadata flags to config=ci.
Added custom tags metadata to help differentiate invocations based on
workflow (bazel vs v8) and os (linux/macos/windows).

Enabled users to override the default values in .bazelrc by using a
user.bazelrc file locally.
Added user.bazelrc to gitignore.

.github/workflows/bazel.yml

@@ -144,10 +144,7 @@ jobs:
           bazel_args=(
             test
             --test_verbose_timeout_warnings
-            --build_metadata=REPO_URL=https://github.com/openai/codex.git
             --build_metadata=COMMIT_SHA=$(git rev-parse HEAD)
-            --build_metadata=ROLE=CI
-            --build_metadata=VISIBILITY=PUBLIC
           )
 
           bazel_targets=(
@@ -164,6 +161,13 @@ jobs:
             bazel_args+=("--test_env=CODEX_JS_REPL_NODE_PATH=${node_bin}")
           fi
 
+          ci_config=ci-linux
+          if [[ "${RUNNER_OS:-}" == "macOS" ]]; then
+            ci_config=ci-macos
+          elif [[ "${RUNNER_OS:-}" == "Windows" ]]; then
+            ci_config=ci-windows
+          fi
+
           if [[ -n "${BUILDBUDDY_API_KEY:-}" ]]; then
             echo "BuildBuddy API key is available; using remote Bazel configuration."
             # Work around Bazel 9 remote repo contents cache / overlay materialization failures
@@ -173,8 +177,8 @@ jobs:
             set +e
             bazel $BAZEL_STARTUP_ARGS \
               --noexperimental_remote_repo_contents_cache \
-              --bazelrc=.github/workflows/ci.bazelrc \
               "${bazel_args[@]}" \
+              "--config=${ci_config}" \
               "--remote_header=x-buildbuddy-api-key=$BUILDBUDDY_API_KEY" \
               -- \
               "${bazel_targets[@]}" \

.github/workflows/ci.bazelrc

@@ -1,27 +0,0 @@
-common --remote_download_minimal
-common --keep_going
-common --verbose_failures
-
-# Disable disk cache since we have remote one and aren't using persistent workers.
-common --disk_cache=
-
-# Rearrange caches on Windows so they're on the same volume as the checkout.
-common:windows --repo_contents_cache=D:/a/.cache/bazel-repo-contents-cache
-common:windows --repository_cache=D:/a/.cache/bazel-repo-cache
-
-# We prefer to run the build actions entirely remotely so we can dial up the concurrency.
-# We have platform-specific tests, so we want to execute the tests on all platforms using the strongest sandboxing available on each platform.
-
-# On linux, we can do a full remote build/test, by targeting the right (x86/arm) runners, so we have coverage of both.
-# Linux crossbuilds don't work until we untangle the libc constraint mess.
-common:linux --config=remote
-common:linux --strategy=remote
-common:linux --platforms=//:rbe
-
-# On mac, we can run all the build actions remotely but test actions locally.
-common:macos --config=remote
-common:macos --strategy=remote
-common:macos --strategy=TestRunner=darwin-sandbox,local
-
-# On windows we cannot cross-build the tests but run them locally due to what appears to be a Bazel bug
-# (windows vs unix path confusion)

.github/workflows/rusty-v8-release.yml

@@ -116,8 +116,8 @@ jobs:
 
           bazel \
             --noexperimental_remote_repo_contents_cache \
-            --bazelrc=.github/workflows/v8-ci.bazelrc \
             "${bazel_args[@]}" \
+            --config=ci-v8 \
             "--remote_header=x-buildbuddy-api-key=${BUILDBUDDY_API_KEY}"
 
       - name: Stage release pair

.github/workflows/v8-canary.yml

@@ -108,8 +108,8 @@ jobs:
 
           bazel \
             --noexperimental_remote_repo_contents_cache \
-            --bazelrc=.github/workflows/v8-ci.bazelrc \
             "${bazel_args[@]}" \
+            --config=ci-v8 \
             "--remote_header=x-buildbuddy-api-key=${BUILDBUDDY_API_KEY}"
 
       - name: Stage release pair

.github/workflows/v8-ci.bazelrc

@@ -1,5 +0,0 @@
-import %workspace%/.github/workflows/ci.bazelrc
-
-common --build_metadata=REPO_URL=https://github.com/openai/codex.git
-common --build_metadata=ROLE=CI
-common --build_metadata=VISIBILITY=PUBLIC