feat: Implement financial engine for commission and tax calculations

- Added new configuration keys for appointment and upgrade commissions, tax settings, and SMS panel fee in SiteConfigController and SiteConfigRepository.
- Introduced CommissionService to handle commission calculations for appointments and subscriptions, including tax deductions and SMS fees.
- Created FinancialBreakdown entity and repository to log financial transactions.
- Updated PaymentController to process commissions upon successful payments for appointments and subscriptions.
- Developed FinancialReportPage in the admin panel to display financial breakdowns and summaries.
- Added database migration for the new financial_breakdowns table.

docs/api/payment.md

@@ -106,6 +106,8 @@ Initiate payment for an appointment. Returns a redirect URL to the payment gatew
 ```
 
 > **On successful callback** for an appointment payment, the booking is transitioned `pending → confirmed` (its 15-minute `expires_at` is cleared) and a confirmation SMS is dispatched to the patient's mobile. If the booking already lapsed to `expired` before payment confirmed, it is **not** re-confirmed (the transition is rejected) — handle refund out of band.
+>
+> **پورسانت نماینده:** اگر پزشک نوبت `representation_id` داشته باشد و `appointment_commission_enabled=1` باشد، پس از confirm شدن `CommissionService` هزینه پنل پیامک و مالیات را کسر و سهم نماینده را به کیف‌پولش واریز می‌کند (ردیف `FinancialBreakdown` ثبت می‌شود). برای پرداخت اشتراک هم اگر `upgrade_commission_enabled=1` و پزشک/کلینیک `representation_id` داشته باشد همین منطق با درصد `upgrade_commission_percent` اعمال می‌شود. کلیدهای تنظیمات و ترتیب محاسبه در `docs/api/admin.md`.
 
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