Market data sync refinements (#2252)

* Exchange rate syncer implementation

* Security price syncer

* Fix issues with provider API

* Add back prod schedule

* Add back price and exchange rate syncs to account syncs

* Remove unused stock_exchanges table

db/migrate/20250516180846_remove_stock_exchanges.rb

@@ -0,0 +1,11 @@
+class RemoveStockExchanges < ActiveRecord::Migration[7.2]
+  def change
+    drop_table :stock_exchanges do |t|
+      t.string :name, null: false
+      t.string :acronym
+      t.string :mic, null: false
+      t.string :country, null: false
+      t.string :country_code, null: false
+    end
+  end
+end