Add GSP init and AI usage tooling

toolkit/scripts/install.ps1

@@ -0,0 +1,38 @@
+param(
+    [string]$InstallDir = "$HOME\.gsp\bin"
+)
+
+$ErrorActionPreference = "Stop"
+
+$ScriptDir = Split-Path -Parent $MyInvocation.MyCommand.Path
+$ToolkitDir = Resolve-Path -LiteralPath (Join-Path $ScriptDir "..")
+$TargetDir = $ExecutionContext.SessionState.Path.GetUnresolvedProviderPathFromPSPath($InstallDir)
+$TargetExe = Join-Path $TargetDir "gsp.exe"
+
+New-Item -ItemType Directory -Force -Path $TargetDir | Out-Null
+
+Push-Location $ToolkitDir
+try {
+    go build -o $TargetExe .\cmd\gsp
+}
+finally {
+    Pop-Location
+}
+
+$userPath = [Environment]::GetEnvironmentVariable("Path", "User")
+$parts = @()
+if ($userPath) {
+    $parts = $userPath -split ";" | Where-Object { $_ -ne "" }
+}
+
+if ($parts -notcontains $TargetDir) {
+    $newPath = (($parts + $TargetDir) -join ";")
+    [Environment]::SetEnvironmentVariable("Path", $newPath, "User")
+    Write-Host "Installed gsp to $TargetExe"
+    Write-Host "Added $TargetDir to the user PATH. Open a new terminal before running gsp."
+}
+else {
+    Write-Host "Installed gsp to $TargetExe"
+}
+
+& $TargetExe version