Refactor load testing scripts to support Bash and PowerShell

- Updated README.md to reflect changes in load testing commands and added usage examples for Bash scripts.
- Converted PowerShell load testing scripts to Bash equivalents for better cross-platform compatibility.
- Added new Bash scripts: run-loadtests.sh, summarize-artillery.sh, and summarize-k6.sh to mirror existing PowerShell functionality.
- Updated admin-api.js and ws-chat.yml for consistency and improved performance metrics reporting.
- Enhanced error handling and output formatting in summary scripts for better readability.

scripts/loadtest/run-loadtests.sh

@@ -0,0 +1,72 @@
+#!/usr/bin/env bash
+# run-loadtests.sh — Run an artillery (ws) and/or k6 (admin) load-test scenario
+# and write outputs into a dated artifacts folder.
+# Mirrors scripts/loadtest/run-loadtests.ps1.
+#
+# Usage:
+#   ./scripts/loadtest/run-loadtests.sh -s ws   -w 'wss://...'
+#   ./scripts/loadtest/run-loadtests.sh -s admin -a 'https://...' -c 'session=...'
+#   ./scripts/loadtest/run-loadtests.sh -s all  -w 'wss://...' -a 'https://...' -c 'session=...'
+set -euo pipefail
+
+script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+repo_root="$(cd "$script_dir/../.." && pwd)"
+
+SCENARIO="all"
+ARTIFACT_ROOT="artifacts"
+WS_URL="${WS_URL:-}"
+ADMIN_BASE_URL="${ADMIN_BASE_URL:-}"
+ADMIN_SESSION_COOKIE="${ADMIN_SESSION_COOKIE:-}"
+
+usage() {
+  echo "Usage: $0 [-s ws|admin|all] [-w ws_url] [-a admin_base_url] [-c admin_session_cookie] [-r artifact_root]" >&2
+  exit 2
+}
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    -s) SCENARIO="$2"; shift 2;;
+    -w) WS_URL="$2"; shift 2;;
+    -a) ADMIN_BASE_URL="$2"; shift 2;;
+    -c) ADMIN_SESSION_COOKIE="$2"; shift 2;;
+    -r) ARTIFACT_ROOT="$2"; shift 2;;
+    -h|--help) usage;;
+    *) echo "Unknown option: $1" >&2; usage;;
+  esac
+done
+
+case "$SCENARIO" in ws|admin|all) ;; *) echo "Scenario must be ws|admin|all" >&2; exit 2;; esac
+
+if [[ "$SCENARIO" == ws || "$SCENARIO" == all ]] && ! command -v npx >/dev/null 2>&1; then
+  echo "npx is required for ws scenario but was not found in PATH." >&2; exit 1
+fi
+if [[ "$SCENARIO" == admin || "$SCENARIO" == all ]] && ! command -v k6 >/dev/null 2>&1; then
+  echo "k6 is required for admin scenario but was not found in PATH." >&2; exit 1
+fi
+
+if [[ "$ARTIFACT_ROOT" = /* ]]; then artifact_base="$ARTIFACT_ROOT"; else artifact_base="$repo_root/$ARTIFACT_ROOT"; fi
+artifact_dir="$artifact_base/$(date +%Y-%m-%d_%H%M%S)"
+mkdir -p "$artifact_dir"
+
+if [[ "$SCENARIO" == ws || "$SCENARIO" == all ]]; then
+  [[ -n "$WS_URL" ]] || { echo "WS_URL is required for ws scenario. Pass -w or set \$WS_URL." >&2; exit 1; }
+  ws_out="$artifact_dir/ws-chat-report.json"
+  ws_sum="$artifact_dir/ws-chat-summary.txt"
+  echo "== Running artillery ws scenario =="
+  WS_URL="$WS_URL" npx artillery run "$script_dir/ws-chat.yml" --output "$ws_out"
+  "$script_dir/summarize-artillery.sh" "$ws_out" | tee "$ws_sum"
+fi
+
+if [[ "$SCENARIO" == admin || "$SCENARIO" == all ]]; then
+  [[ -n "$ADMIN_BASE_URL" ]] || { echo "ADMIN_BASE_URL is required for admin scenario. Pass -a or set \$ADMIN_BASE_URL." >&2; exit 1; }
+  [[ -n "$ADMIN_SESSION_COOKIE" ]] || { echo "ADMIN_SESSION_COOKIE is required for admin scenario. Pass -c or set \$ADMIN_SESSION_COOKIE." >&2; exit 1; }
+  admin_sum="$artifact_dir/admin-api-summary.json"
+  admin_out="$artifact_dir/admin-api-output.txt"
+  admin_ep_sum="$artifact_dir/admin-api-endpoint-summary.txt"
+  echo "== Running k6 admin scenario =="
+  ADMIN_BASE_URL="$ADMIN_BASE_URL" ADMIN_SESSION_COOKIE="$ADMIN_SESSION_COOKIE" \
+    k6 run --summary-export "$admin_sum" "$script_dir/admin-api.js" | tee "$admin_out"
+  "$script_dir/summarize-k6.sh" "$admin_sum" | tee "$admin_ep_sum"
+fi
+
+echo "Artifacts written to $artifact_dir"