Start private space setup when there is no private space set

This change handles as below based on if private space already exists on device:
1. If PS doesn't exist then start the setup flow which shows a PS education screen. On setup button creates the private space.
2. If PS already exists on device then display PS settings page.

Bug: 299069146
Test: atest PrivateSpaceSettingsAuthenticatorTest
Change-Id: I46bdbaeb0210fd5b41a426f852e3f455b62c1c29
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 1bd37da..ffdc7e8 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -4991,6 +4991,11 @@
             </intent-filter>
         </provider>
 
+        <activity
+            android:name=".privatespace.PrivateSpaceSetupActivity"
+            android:theme="@style/GlifV3Theme.Light"
+            android:exported="false" />
+
         <activity android:name=".privatespace.PrivateSpaceAuthenticationActivity"
                   android:theme="@*android:style/Theme.DeviceDefault.Settings.Dialog.NoActionBar"
                   android:exported="false"/>