fix: Move system-level activity app settings to the sample config

These entries are currently hard-coded in the manual itself (on the config parameter page that is generated from this config sample file). This PR moves them to the proper place, the config sample file itself.

A separate PR in the docs repo will remove their hard-coded entry in the manual, but this is not dependent on that PR.

Signed-off-by: Josh <josh.t.richards@gmail.com>

Author: joshtrichards

config/config.sample.php

@@ -1282,6 +1282,49 @@
 	'customclient_fdroid'
 		=> 'https://f-droid.org/packages/com.nextcloud.client/',
 
+	/**
+	 * Activity
+	 *
+	 * Options for the activity app.
+	 */
+
+	/**
+	 * Retention of activities.
+	 *
+	 * A daily cron job deletes all activities for all users which are older than
+	 * the number of days specified here.
+	 *
+	 * Defaults to ``365``
+	 */
+
+	'activity_expire_days' => 365,
+
+	/**
+	 * Activities in Team Folders and External Storages.
+	 *
+	 * By default, activities in team folders or external storages are only generated 
+	 * for the current user. This is due to a limitations in current implementations. 
+	 * This config flag makes activities in group folders and external storages work
+	 * like in normal shares (when set to ``true``). WARNING: Enabling this comes with 
+	 * some CRITICAL trade-offs:
+	 *
+	 * - If team folder "Advanced Permissions" (ACLs) are used, activities do not 
+	 *   respect the permissions and therefore all users see all activities, even 
+	 *   for files and directories they do not have access to.
+     * - Users who had access to a team folder, share, or external storage can see 
+	 *   activities in their stream and emails that happen after they are removed 
+	 *   until they log in again.
+     * - Users who are newly added to a team folder, share, or external storage 
+	 *   cannot see activities in their stream or emails that happen after they 
+	 *   are added until they log in again.
+	 * 
+	 * WARNING: Before enabling this, read the warning Activity app chapter.
+	 *
+	 * Defaults to ``false``
+	 **/
+	
+	'activity_use_cached_mountpoints' => false,
+
 	/**
 	 * Apps
 	 *