fix: update E2E test API paths and payloads to match backend

- user-apikey-lifecycle: /api/v1/keys -> /api/v1/api-keys (24 occurrences)
- admin-users: balance payload uses balance+operation+notes
- admin-groups: rate-multiplier already uses correct format

tests/scripts/run-benchmarks.ps1

@@ -0,0 +1,54 @@
+# Sub2API Performance Test Runner
+# Run: .\run-benchmarks.ps1
+
+param(
+    [string]$OutputDir = "..\performance\reports"
+)
+
+$ErrorActionPreference = "Stop"
+$ProjectRoot = Split-Path -Parent $PSScriptRoot
+
+Write-Host "============================================" -ForegroundColor Cyan
+Write-Host "  Sub2API Performance Test Runner" -ForegroundColor Cyan
+Write-Host "============================================" -ForegroundColor Cyan
+
+# Ensure output directory exists
+$OutputPath = Join-Path $ProjectRoot $OutputDir
+if (-not (Test-Path $OutputPath)) {
+    New-Item -ItemType Directory -Path $OutputPath | Out-Null
+}
+
+$Timestamp = Get-Date -Format "yyyy-MM-dd_HH-mm-ss"
+$ReportFile = Join-Path $OutputPath "benchmark_$Timestamp.txt"
+
+Write-Host "`n[1/3] Running Go Benchmarks..." -ForegroundColor Yellow
+Set-Location (Join-Path $ProjectRoot "backend")
+
+# Run all benchmarks
+$benchResult = go test -bench=. -benchmem -count=5 -timeout 300s ./... 2>&1 | Select-String -Pattern "^(Benchmark|PASS|ok|---)"
+
+$benchResult | Out-File -FilePath $ReportFile -Encoding UTF8
+Write-Host "  Results saved to: $ReportFile" -ForegroundColor Green
+
+Write-Host "`n[2/3] Running Handler Benchmarks..." -ForegroundColor Yellow
+$handlerResult = go test -bench=Handler -benchmem -count=3 -timeout 120s ./internal/handler/... 2>&1 | Select-String -Pattern "^(Benchmark|PASS|ok|---)"
+$handlerResult | Out-File -FilePath (Join-Path $OutputPath "handler_bench_$Timestamp.txt") -Encoding UTF8
+
+Write-Host "`n[3/3] Running Service Benchmarks..." -ForegroundColor Yellow
+$serviceResult = go test -bench=Service -benchmem -count=3 -timeout 120s ./internal/service/... 2>&1 | Select-String -Pattern "^(Benchmark|PASS|ok|---)"
+$serviceResult | Out-File -FilePath (Join-Path $OutputPath "service_bench_$Timestamp.txt") -Encoding UTF8
+
+Write-Host "`n============================================" -ForegroundColor Cyan
+Write-Host "  Benchmark Results Summary" -ForegroundColor Cyan
+Write-Host "============================================" -ForegroundColor Cyan
+
+# Parse and display key results
+Write-Host "`nKey Metrics:" -ForegroundColor White
+$benchResult | ForEach-Object {
+    if ($_ -match "Benchmark.*-(\d+)\s+(\d+)\s+ns/op") {
+        Write-Host "  $_" -ForegroundColor Gray
+    }
+}
+
+Write-Host "`nBenchmark tests complete!" -ForegroundColor Green
+Write-Host "Reports saved to: $OutputPath" -ForegroundColor Cyan