Add tray browser enrollment with region picker

The tray helper carried a ServerURL default that nothing read.
Unenrolled users can now open the console /enroll page from the
menu: US, EU, or self-hosted in production, or --server for dev.

Signed-off-by: Ludovic Vielle <ludovic@probo.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

pkg/deviceagent/tray/enroll.go

@@ -0,0 +1,57 @@
+// Copyright (c) 2026 Probo Inc <hello@probo.com>.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+//go:build (darwin && cgo) || windows
+
+package tray
+
+import (
+	"fmt"
+	"os"
+
+	"go.probo.inc/probo/pkg/deviceagent"
+)
+
+func openConsoleEnroll(serverURL string) {
+	enrollURL, err := deviceagent.ConsoleEnrollURL(serverURL)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "cannot open enrollment page: %v\n", err)
+		return
+	}
+
+	if err := openBrowser(enrollURL); err != nil {
+		fmt.Fprintf(os.Stderr, "cannot open browser: %v\n", err)
+	}
+}
+
+func openSelfHostedEnroll() {
+	hostname, ok := promptSelfHostedHostname()
+	if !ok {
+		return
+	}
+
+	normalized, err := deviceagent.NormalizeServerURL(hostname)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "invalid hostname: %v\n", err)
+		return
+	}
+
+	openConsoleEnroll(normalized)
+}