use counter culture and move the optimisation under feature flag

db/migrate/20260203062506_add_conversations_count_to_accounts.rb

@@ -1,5 +0,0 @@
-class AddConversationsCountToAccounts < ActiveRecord::Migration[7.1]
-  def change
-    add_column :accounts, :conversations_count, :integer, default: 0, null: false
-  end
-end

db/migrate/20260203062518_backfill_conversations_count.rb

@@ -1,11 +0,0 @@
-class BackfillConversationsCount < ActiveRecord::Migration[7.1]
-  def up
-    Account.find_each do |account|
-      Account.reset_counters(account.id, :conversations)
-    end
-  end
-
-  def down
-    # No-op
-  end
-end

db/migrate/20260203125142_add_status_conversation_counters_to_accounts.rb

@@ -0,0 +1,8 @@
+class AddStatusConversationCountersToAccounts < ActiveRecord::Migration[7.1]
+  def change
+    add_column :accounts, :open_conversations_count, :integer, default: 0, null: false
+    add_column :accounts, :resolved_conversations_count, :integer, default: 0, null: false
+    add_column :accounts, :pending_conversations_count, :integer, default: 0, null: false
+    add_column :accounts, :snoozed_conversations_count, :integer, default: 0, null: false
+  end
+end

db/migrate/20260203125200_backfill_status_conversation_counters.rb

@@ -0,0 +1,25 @@
+class BackfillStatusConversationCounters < ActiveRecord::Migration[7.1]
+  def up
+    Account.find_each do |account|
+      # Count conversations by status for this account
+      open_count = account.conversations.open.count
+      resolved_count = account.conversations.resolved.count
+      pending_count = account.conversations.pending.count
+      snoozed_count = account.conversations.snoozed.count
+
+      # Update the counter cache columns
+      # rubocop:disable Rails/SkipsModelValidations
+      account.update_columns(
+        open_conversations_count: open_count,
+        resolved_conversations_count: resolved_count,
+        pending_conversations_count: pending_count,
+        snoozed_conversations_count: snoozed_count
+      )
+      # rubocop:enable Rails/SkipsModelValidations
+    end
+  end
+
+  def down
+    # No-op
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2026_02_03_062518) do
+ActiveRecord::Schema[7.1].define(version: 2026_02_03_125200) do
   # These extensions should be enabled to support this database
   enable_extension "pg_stat_statements"
   enable_extension "pg_trgm"
@@ -73,7 +73,10 @@ ActiveRecord::Schema[7.1].define(version: 2026_02_03_062518) do
     t.integer "status", default: 0
     t.jsonb "internal_attributes", default: {}, null: false
     t.jsonb "settings", default: {}
-    t.integer "conversations_count", default: 0, null: false
+    t.integer "open_conversations_count", default: 0, null: false
+    t.integer "resolved_conversations_count", default: 0, null: false
+    t.integer "pending_conversations_count", default: 0, null: false
+    t.integer "snoozed_conversations_count", default: 0, null: false
     t.index ["status"], name: "index_accounts_on_status"
   end