Add scripts/dev-up.ps1 to launch the whole local dev stack

Single command brings up Postgres (via dev-db.ps1), the backend API,
and the Vite frontend. API and frontend each get their own PowerShell
window so logs do not interleave and Ctrl+C only kills the intended
process. Email links print to the API window via LoggingEmailSender.

scripts/dev-up.ps1

@@ -0,0 +1,49 @@
+#!/usr/bin/env pwsh
+<#
+.SYNOPSIS
+    Bring up the full local dev stack: Postgres + backend API + Vite frontend.
+
+.DESCRIPTION
+    Starts the dev Postgres container (via dev-db.ps1), then spawns the API and
+    frontend in their own PowerShell windows so each keeps its own scrollback
+    and Ctrl+C only kills the intended process. The API log window is where
+    invite/reset email links print (LoggingEmailSender output).
+
+    Stop everything by closing the two spawned windows. The DB stays up across
+    runs; use './scripts/dev-db.ps1 stop' or 'reset' to manage it explicitly.
+
+.EXAMPLE
+    ./scripts/dev-up.ps1
+#>
+param()
+
+$ErrorActionPreference = 'Stop'
+
+$RepoRoot = Resolve-Path "$PSScriptRoot/.."
+
+# 1. Database
+& "$PSScriptRoot/dev-db.ps1" start
+
+# 2. Backend API. Tag the window title so it's easy to find when stopping.
+Write-Host "Launching backend in a new window..." -ForegroundColor Cyan
+Start-Process pwsh -ArgumentList @(
+    '-NoExit',
+    '-Command',
+    "`$Host.UI.RawUI.WindowTitle = 'YesChef API'; dotnet run --project '$RepoRoot/src/backend/YesChef.Api'"
+)
+
+# 3. Frontend (Vite dev server, with the existing /api + /hubs proxy).
+Write-Host "Launching frontend in a new window..." -ForegroundColor Cyan
+Start-Process pwsh -ArgumentList @(
+    '-NoExit',
+    '-Command',
+    "`$Host.UI.RawUI.WindowTitle = 'YesChef Frontend'; npm --prefix '$RepoRoot/src/frontend' run dev"
+)
+
+Write-Host ""
+Write-Host "Stack is starting. URLs:" -ForegroundColor Green
+Write-Host "  Frontend: http://localhost:5173"
+Write-Host "  API     : http://localhost:5291"
+Write-Host ""
+Write-Host "Invite and password-reset links print to the API window (LoggingEmailSender)."
+Write-Host "Close the two spawned windows to stop. DB remains up; manage with scripts/dev-db.ps1."