refactor: update admin columns for Ahoy models

- Removed user_id, city, country, and region columns
- Added visit_id, visit_token, referrer, landing_page,
  browser, os, and device_type columns

This refactor improves the administrative interface for Ahoy
models by updating the displayed attributes to better suit
the current application requirements. It also aligns the
displayed data with the available attributes in the Ahoy
tracking system, making it easier for administrators to
review relevant information.

app/admin/ahoy_events.rb

@@ -23,7 +23,8 @@ ActiveAdmin.register Ahoy::Event do
     column :name
     column :time
     column :properties
-    column :user_id
+    # column :user_id
+    column :visit_id
   end
 
   filter :name

app/admin/ahoy_visits.rb

@@ -25,9 +25,17 @@ ActiveAdmin.register Ahoy::Visit do
     column :ip
     column :user_agent
     column :started_at
-    column :city
+    # column :city
-    column :country
+    # column :country
-    column :region
+    # column :region
+    column :visit_token
+    column :user_agent
+    column :referrer
+    column :landing_page
+    column :browser
+    column :os
+    column :device_type
+    column :started_at
   end
 
   filter :started_at