Feat: Benchmark CLI additions and documentation (#12536)

### What problem does this PR solve?

This PR adds a dedicated HTTP benchmark CLI for RAGFlow chat and
retrieval endpoints so we can measure latency/QPS.

### Type of change

- [x] Documentation Update
- [x] Other (please describe): Adds a CLI benchmarking tool for
chat/retrieval latency/QPS

---------

Co-authored-by: Liu An <asiro@qq.com>

test/benchmark/run_retrieval_chat.sh

@@ -0,0 +1,98 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
+
+: "${ZHIPU_AI_API_KEY:?ZHIPU_AI_API_KEY is required}"
+
+BASE_URL="http://127.0.0.1:9380"
+LOGIN_EMAIL="qa@infiniflow.org"
+LOGIN_PASSWORD="123"
+DATASET_PAYLOAD='{"name":"bench_dataset","embedding_model":"BAAI/bge-small-en-v1.5@Builtin"}'
+CHAT_PAYLOAD='{"name":"bench_chat","llm":{"model_name":"glm-4-flash@ZHIPU-AI"}}'
+DATASET_ID=""
+
+cleanup_dataset() {
+  if [[ -z "${DATASET_ID}" ]]; then
+    return
+  fi
+  set +e
+  BENCH_BASE_URL="${BASE_URL}" \
+  BENCH_LOGIN_EMAIL="${LOGIN_EMAIL}" \
+  BENCH_LOGIN_PASSWORD="${LOGIN_PASSWORD}" \
+  BENCH_DATASET_ID="${DATASET_ID}" \
+  PYTHONPATH="${REPO_ROOT}/test" uv run python - <<'PY'
+import os
+import sys
+
+from benchmark import auth
+from benchmark.auth import AuthError
+from benchmark.dataset import delete_dataset
+from benchmark.http_client import HttpClient
+
+base_url = os.environ["BENCH_BASE_URL"]
+email = os.environ["BENCH_LOGIN_EMAIL"]
+password = os.environ["BENCH_LOGIN_PASSWORD"]
+dataset_id = os.environ["BENCH_DATASET_ID"]
+
+client = HttpClient(base_url=base_url, api_version="v1")
+
+try:
+    password_enc = auth.encrypt_password(password)
+    nickname = email.split("@")[0]
+    try:
+        auth.register_user(client, email, nickname, password_enc)
+    except AuthError as exc:
+        print(f"Register warning: {exc}", file=sys.stderr)
+    login_token = auth.login_user(client, email, password_enc)
+    client.login_token = login_token
+    client.api_key = auth.create_api_token(client, login_token, None)
+    delete_dataset(client, dataset_id)
+except Exception as exc:
+    print(f"Cleanup warning: failed to delete dataset {dataset_id}: {exc}", file=sys.stderr)
+PY
+}
+
+trap cleanup_dataset EXIT
+
+retrieval_output="$(PYTHONPATH="${REPO_ROOT}/test" uv run -m benchmark retrieval \
+  --base-url "${BASE_URL}" \
+  --allow-register \
+  --login-email "${LOGIN_EMAIL}" \
+  --login-password "${LOGIN_PASSWORD}" \
+  --bootstrap-llm \
+  --llm-factory ZHIPU-AI \
+  --llm-api-key "${ZHIPU_AI_API_KEY}" \
+  --dataset-name "bench_dataset" \
+  --dataset-payload "${DATASET_PAYLOAD}" \
+  --document-path "${SCRIPT_DIR}/test_docs/Doc1.pdf" \
+  --document-path "${SCRIPT_DIR}/test_docs/Doc2.pdf" \
+  --document-path "${SCRIPT_DIR}/test_docs/Doc3.pdf" \
+  --iterations 10 \
+  --concurrency 8 \
+  --question "What does RAG mean?")"
+printf '%s\n' "${retrieval_output}"
+
+DATASET_ID="$(printf '%s\n' "${retrieval_output}" | sed -n 's/^Created Dataset ID: //p' | head -n 1)"
+if [[ -z "${DATASET_ID}" ]]; then
+  echo "Failed to parse Created Dataset ID from retrieval output." >&2
+  exit 1
+fi
+
+PYTHONPATH="${REPO_ROOT}/test" uv run -m benchmark chat \
+  --base-url "${BASE_URL}" \
+  --allow-register \
+  --login-email "${LOGIN_EMAIL}" \
+  --login-password "${LOGIN_PASSWORD}" \
+  --bootstrap-llm \
+  --llm-factory ZHIPU-AI \
+  --llm-api-key "${ZHIPU_AI_API_KEY}" \
+  --dataset-id "${DATASET_ID}" \
+  --chat-name "bench_chat" \
+  --chat-payload "${CHAT_PAYLOAD}" \
+  --message "What is the purpose of RAGFlow?" \
+  --model "glm-4-flash@ZHIPU-AI" \
+  --iterations 10 \
+  --concurrency 8 \
+  --teardown