style: split migration into smaller methods to reduce method length

db/migrate/20260211145813_create_reporting_events_rollup.rb

@@ -2,6 +2,13 @@ class CreateReportingEventsRollup < ActiveRecord::Migration[7.1]
   disable_ddl_transaction!
 
   def change
+    create_rollups_table
+    add_rollups_indexes
+  end
+
+  private
+
+  def create_rollups_table
     create_table :reporting_events_rollups do |t|
       t.integer :account_id, null: false
       t.date :date, null: false
@@ -14,24 +21,19 @@ class CreateReportingEventsRollup < ActiveRecord::Migration[7.1]
 
       t.timestamps
     end
+  end
 
-    # Unique index for upsert conflict resolution
+  def add_rollups_indexes
     add_index :reporting_events_rollups,
               [:account_id, :date, :dimension_type, :dimension_id, :metric],
-              unique: true,
-              name: 'index_rollup_unique_key',
-              algorithm: :concurrently
+              unique: true, name: 'index_rollup_unique_key', algorithm: :concurrently
 
-    # Query index for timeseries (date range scans)
     add_index :reporting_events_rollups,
               [:account_id, :metric, :date],
-              name: 'index_rollup_timeseries',
-              algorithm: :concurrently
+              name: 'index_rollup_timeseries', algorithm: :concurrently
 
-    # Query index for summaries (dimension scans)
     add_index :reporting_events_rollups,
               [:account_id, :dimension_type, :date],
-              name: 'index_rollup_summary',
-              algorithm: :concurrently
+              name: 'index_rollup_summary', algorithm: :concurrently
   end
 end