Fix duplicate FIX orders and lowercase side field

Add new securities and use real prices in FIX UI order entry

Fix Order Entry connect + back arrows

FIX UI: convert to AJAX - fix connect/disconnect/order broken under nginx

Fix frontend disconnected, FIX UI reloader, add dashboard clock

Chart: volume dots, price dots, multi-symbol volumes; FIX UI back button

Add mobile-responsive layout to dashboard and FIX UI client

Add NBG security and restrict symbol entry to known securities

Initial commit: StockEx trading platform