Replace shared bearer token with registered Ed25519 client keys.

tools/install-native-host.ps1

@@ -16,14 +16,9 @@ if (-not (Test-Path $CmdPath)) {
 }
 
 New-Item -ItemType Directory -Force -Path $StateDir | Out-Null
-if (-not (Test-Path $TokenPath) -or -not (Get-Content -Raw $TokenPath).Trim()) {
-    $bytes = New-Object byte[] 32
-    [System.Security.Cryptography.RandomNumberGenerator]::Create().GetBytes($bytes)
-    $token = -join ($bytes | ForEach-Object { $_.ToString("x2") })
-    [System.IO.File]::WriteAllText($TokenPath, $token)
-    Write-Host "wrote $TokenPath"
-} else {
-    Write-Host "kept existing token at $TokenPath"
+if (Test-Path $TokenPath) {
+    Remove-Item -Force $TokenPath
+    Write-Host "removed leftover shared token $TokenPath"
 }
 
 $manifest = @{
@@ -42,6 +37,6 @@ Set-ItemProperty -Path $regPath -Name "(default)" -Value $ManifestPath
 Write-Host "registered $regPath"
 
 Write-Host ""
-Write-Host "Next: in Firefox open about:debugging#/runtime/this-firefox"
-Write-Host "Load Temporary Add-on and pick extension\manifest.json"
-Write-Host "Token is read from $TokenPath (Authorization: Bearer ...)"
+Write-Host "Register a client key for tooling (private key stays out of $StateDir):"
+Write-Host "  python tools\register_client.py add --name cursor-agent --write-key `$HOME\.fab\cursor-agent.json"
+Write-Host "Then load the extension and set FAB_KEY_FILE to that path."