feat: add shadcn admin workspace

stop-services.ps1

@@ -1,6 +1,7 @@
 param(
   [switch]$FrontendOnly,
   [switch]$BackendOnly,
+  [switch]$AdminOnly,
   [switch]$McpOnly,
   [switch]$WithMcp
 )
@@ -9,8 +10,8 @@ $ErrorActionPreference = "Stop"
 
 $repoRoot = Split-Path -Parent $MyInvocation.MyCommand.Path
 
-if (@($FrontendOnly, $BackendOnly, $McpOnly).Where({ $_ }).Count -gt 1) {
-  throw "Use only one of -FrontendOnly, -BackendOnly, or -McpOnly."
+if (@($FrontendOnly, $BackendOnly, $AdminOnly, $McpOnly).Where({ $_ }).Count -gt 1) {
+  throw "Use only one of -FrontendOnly, -BackendOnly, -AdminOnly, or -McpOnly."
 }
 
 function Stop-RepoShells {
@@ -75,6 +76,11 @@ function Stop-Backend {
   Stop-PortOwner -Port 5150 -Label "backend"
 }
 
+function Stop-Admin {
+  Stop-RepoShells -ScriptName "start-admin.ps1"
+  Stop-PortOwner -Port 4322 -Label "admin"
+}
+
 function Stop-Mcp {
   Stop-RepoShells -ScriptName "start-mcp.ps1"
   Stop-PortOwner -Port 5151 -Label "MCP"
@@ -90,13 +96,19 @@ if ($BackendOnly) {
   exit 0
 }
 
+if ($AdminOnly) {
+  Stop-Admin
+  exit 0
+}
+
 if ($McpOnly) {
   Stop-Mcp
   exit 0
 }
 
-Write-Host "[stop] Stopping frontend and backend services..." -ForegroundColor Cyan
+Write-Host "[stop] Stopping frontend, admin, and backend services..." -ForegroundColor Cyan
 Stop-Frontend
+Stop-Admin
 Stop-Backend
 
 if ($WithMcp) {