fix: secure GitLab example Git authentication

.changeset/quiet-gitlab-credentials.md

@@ -0,0 +1,5 @@
+---
+"openwiki": patch
+---
+
+Use an ephemeral credential helper in the GitLab CI example so push credentials cannot persist in remote URLs or appear under shell tracing.

examples/openwiki-update.gitlab-ci.yml

@@ -21,7 +21,26 @@ openwiki_update:
     - git checkout -b "$OPENWIKI_BRANCH"
     - git add openwiki AGENTS.md CLAUDE.md .github/workflows/openwiki-update.yml
     - git commit -m "docs: update OpenWiki"
-    - git push "https://oauth2:${OPENWIKI_GITLAB_TOKEN}@${CI_SERVER_HOST}/${CI_PROJECT_PATH}.git" "$OPENWIKI_BRANCH"
+    - |
+      # Configure OPENWIKI_GITLAB_TOKEN as a protected, masked CI/CD variable.
+      # Keep tracing disabled while the temporary helper can read the token.
+      set +x
+      credential_helper="$(mktemp)"
+      trap 'rm -f "$credential_helper"' EXIT
+      chmod 700 "$credential_helper"
+      cat > "$credential_helper" <<'EOF'
+      #!/bin/sh
+      case "$1" in
+        get)
+          printf 'username=%s\n' oauth2
+          printf 'password=%s\n' "$OPENWIKI_GITLAB_TOKEN"
+          ;;
+      esac
+      EOF
+      git -c credential.helper= -c credential.helper="$credential_helper" \
+        push "https://${CI_SERVER_HOST}/${CI_PROJECT_PATH}.git" "$OPENWIKI_BRANCH"
+      rm -f "$credential_helper"
+      trap - EXIT
     - |
       curl --fail --request POST \
         --header "PRIVATE-TOKEN: ${OPENWIKI_GITLAB_TOKEN}" \

test/gitlab-example-security.test.ts

@@ -0,0 +1,27 @@
+import { readFile } from "node:fs/promises";
+import { describe, expect, test } from "vitest";
+import { parse } from "yaml";
+
+const examplePath = new URL(
+  "../examples/openwiki-update.gitlab-ci.yml",
+  import.meta.url,
+);
+
+describe("GitLab CI example", () => {
+  test("keeps Git credentials out of remote URLs and traced commands", async () => {
+    const example = await readFile(examplePath, "utf8");
+    const config = parse(example) as {
+      openwiki_update?: { script?: unknown[] };
+    };
+
+    expect(config.openwiki_update?.script).toBeInstanceOf(Array);
+    expect(example).not.toMatch(/https?:\/\/[^/\s]+@/u);
+    expect(example).toContain("set +x");
+    expect(example).toContain('credential.helper="$credential_helper"');
+    expect(example).toContain("<<'EOF'");
+    expect(example).toContain('"$OPENWIKI_GITLAB_TOKEN"');
+    expect(example).toContain(
+      'push "https://${CI_SERVER_HOST}/${CI_PROJECT_PATH}.git"',
+    );
+  });
+});