remote-activity: Display latest audit log update for remote server.

Since the latest end time for reported active users on a remote
server is not used to determine if a remote server has current
data for billing purposes, we instead display the last audit log
update datetime for the remote server object.

Removes the note in the remote activity key about the Zulip
version.

Also adds a sum in the total row for mobile push notifications
sent.

analytics/views/remote_activity.py

@@ -36,8 +36,7 @@ def get_remote_server_activity(request: HttpRequest) -> HttpResponse:
         icount as (
             select
                 icount_id.server_id,
-                value as latest_value,
-                end_time as latest_end_time
+                value as latest_value
             from icount_id
             join zilencer_remoteinstallationcount
             on max_count_id = zilencer_remoteinstallationcount.id
@@ -64,9 +63,9 @@ def get_remote_server_activity(request: HttpRequest) -> HttpResponse:
             rserver.hostname,
             rserver.contact_email,
             rserver.last_version,
+            rserver.last_audit_log_update,
             latest_value,
             push_user_count,
-            latest_end_time,
             push_forwarded_count
         from zilencer_remotezulipserver rserver
         left join icount on icount.server_id = rserver.id
@@ -82,9 +81,9 @@ def get_remote_server_activity(request: HttpRequest) -> HttpResponse:
         "Hostname",
         "Contact email",
         "Zulip version",
+        "Last audit log update",
         "Analytics users",
         "Mobile users",
-        "Last update time",
         "Mobile pushes forwarded",
         "Plan name",
         "Plan status",
@@ -96,7 +95,7 @@ def get_remote_server_activity(request: HttpRequest) -> HttpResponse:
 
     rows = get_query_data(query)
     total_row = []
-    totals_columns = [4, 5]
+    totals_columns = [5, 6, 7]
     plan_data_by_remote_server = get_plan_data_by_remote_server()
 
     for row in rows:
@@ -121,7 +120,7 @@ def get_remote_server_activity(request: HttpRequest) -> HttpResponse:
         links = stats + " " + support
         row.append(links)
     for i, col in enumerate(cols):
-        if col == "Last update time":
+        if col == "Last audit log update":
             fix_rows(rows, i, format_date_for_activity_reports)
         if col in ["Mobile users", "Mobile pushes forwarded"]:
             fix_rows(rows, i, format_none_as_zero)

templates/analytics/remote_activity_key.html

@@ -1,6 +1,5 @@
 <h4>Chart key:</h4>
 <ul>
-    <li><strong>Zulip version</strong> - as of last update time</li>
     <li><strong>Mobile pushes forwarded</strong> - last 7 days, including today's current count</li>
     <li><strong>ARR</strong> (annual recurring revenue) - the number of users they are paying for * annual price/user</li>
     <li><strong>Links</strong>