Fix start.ps1 to use correct venv paths matching start.sh

Co-authored-by: pamelafox <297042+pamelafox@users.noreply.github.com>

Author: Copilot

app/start.ps1

@@ -1,19 +1,21 @@
-Write-Host 'Creating python virtual environment "backend/backend_env"'
+Set-Location ../
+
+Write-Host 'Creating python virtual environment ".venv"'
 $pythonCmd = Get-Command python -ErrorAction SilentlyContinue
 if (-not $pythonCmd) {
   # fallback to python3 if python not found
   $pythonCmd = Get-Command python3 -ErrorAction SilentlyContinue
 }
-Start-Process -FilePath ($pythonCmd).Source -ArgumentList "-m venv ./backend/backend_env" -Wait -NoNewWindow
+Start-Process -FilePath ($pythonCmd).Source -ArgumentList "-m venv .venv" -Wait -NoNewWindow
 
 Write-Host ""
 Write-Host "Restoring backend python packages"
 Write-Host ""
 
-$venvPythonPath = "./venv/scripts/python.exe"
+$venvPythonPath = "./.venv/Scripts/python.exe"
 if (Test-Path -Path "/usr") {
   # fallback to Linux venv path
-  $venvPythonPath = "./venv/bin/python"
+  $venvPythonPath = "./.venv/bin/python"
 }
 
 Start-Process -FilePath $venvPythonPath -ArgumentList "-m pip install -r app/backend/requirements.txt" -Wait -NoNewWindow
@@ -25,7 +27,7 @@ if ($LASTEXITCODE -ne 0) {
 Write-Host ""
 Write-Host "Restoring frontend npm packages"
 Write-Host ""
-Set-Location ../frontend
+Set-Location app/frontend
 npm install
 if ($LASTEXITCODE -ne 0) {
     Write-Host "Failed to restore frontend npm packages"
@@ -46,6 +48,13 @@ Write-Host "Starting backend"
 Write-Host ""
 Set-Location ../backend
 
+# Update venv path for backend directory
+$venvPythonPath = "../../.venv/Scripts/python.exe"
+if (Test-Path -Path "/usr") {
+  # fallback to Linux venv path
+  $venvPythonPath = "../../.venv/bin/python"
+}
+
 $port = 50505
 $hostname = "localhost"
 Start-Process -FilePath $venvPythonPath -ArgumentList "-m quart --app main:app run --port $port --host $hostname --reload" -Wait -NoNewWindow