fix(dashboard): configured currency + localized widget labels

[hedon77]

Problem

Dashboard admina pokazywał kwoty ze znakiem \$\ mimo domyślnej waluty PLN — bo widgety \BillingWidget\ i \OrdersWidget\ miały hardcoded '$'.

Zmiana

Zamieniono '$'.number_format(...)\ na helper \money_fmt(...), który używa waluty domyślnej z \Currency::getDefault()\ (prefix + suffix). Kwoty dostosowują się do skonfigurowanej waluty (np. \1200.00 zł).

• \�pp/Widgets/BillingWidget.php\ — 4 kwoty (dzisiaj/miesiąc/rok/całościowo)
• \�pp/Widgets/OrdersWidget.php\ — kwota zamówienia

[Panelica]

Merged — thank you. Killing the hardcoded $ and the inline English in the widgets was overdue; routing everything through money_fmt() and __('admin.dashboard.*') is exactly right, and I confirmed the money_fmt / invoice_status_label / company_name helpers all exist on main.

One thing I completed on merge: the 42 new admin.dashboard.* keys landed in en + pl only, which would have failed our TranslationParityTest (every en key must exist in pl/tr/zh) and the SimplifiedChineseTranslationTest (zh must mirror en's structure). I added the Turkish and Simplified Chinese translations and realigned zh — follow-up commit 09b7c5c. Full suite is green (2333 passing).

For future PRs that touch lang/: adding tr and zh alongside en/pl keeps those two tests green — happy to take them exactly as you did here and fill the rest in on our side, just flagging it so you know why the extra commit appeared.