Merge branch 'develop' into codex/cw-4998-disable-inbox

db/migrate/20260622000000_add_account_created_at_index_to_calls.rb

@@ -0,0 +1,7 @@
+class AddAccountCreatedAtIndexToCalls < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+
+  def change
+    add_index :calls, [:account_id, :created_at], algorithm: :concurrently
+  end
+end

db/migrate/20260630000000_add_sender_created_index_to_messages.rb

@@ -0,0 +1,21 @@
+class AddSenderCreatedIndexToMessages < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+
+  # Adds created_at to the (sender_type, sender_id) index so per-assistant
+  # windowed lookups (Captain Overview stats) can range-scan the time slice
+  # instead of reading every lifetime row and filtering at the heap. The new
+  # index is a left-prefix superset of the old one.
+  #
+  # TODO: drop the now-redundant index_messages_on_sender_type_and_sender_id
+  # once this index has been running in production long enough to confirm it
+  # fully replaces the old one.
+  def up
+    add_index :messages, [:sender_type, :sender_id, :created_at],
+              name: 'index_messages_on_sender_and_created', algorithm: :concurrently, if_not_exists: true
+  end
+
+  def down
+    remove_index :messages, name: 'index_messages_on_sender_and_created',
+                            algorithm: :concurrently, if_exists: true
+  end
+end