feat(app): add diagnostics and update runtime

scripts/verify.ps1

@@ -0,0 +1,31 @@
+$ErrorActionPreference = 'Stop'
+
+function Invoke-Step {
+  param(
+    [Parameter(Mandatory = $true)][string]$Name,
+    [Parameter(Mandatory = $true)][string]$Command,
+    [Parameter(Mandatory = $true)][string[]]$Arguments
+  )
+
+  Write-Host ""
+  Write-Host "==> $Name"
+  & $Command @Arguments
+  if ($LASTEXITCODE -ne 0) {
+    throw "$Name failed with exit code $LASTEXITCODE"
+  }
+}
+
+Invoke-Step 'Typecheck' 'npm.cmd' @('run', 'typecheck')
+Invoke-Step 'Tests' 'npm.cmd' @('run', 'test:run')
+Invoke-Step 'Lint' 'npm.cmd' @('run', 'lint')
+Invoke-Step 'Build' 'npm.cmd' @('run', 'build')
+
+Write-Host ""
+Write-Host "==> Audit summary"
+& npm.cmd audit --audit-level=moderate
+if ($LASTEXITCODE -ne 0) {
+  Write-Warning 'npm audit reported vulnerabilities. See the output above; verification gates still passed.'
+}
+
+Write-Host ""
+Write-Host "Verification complete."