many fixes and improvements - rework for modules/ and common/

feat(emailer): add Postmark and Resend providers

Stripe.md

@@ -0,0 +1,30 @@
+# Stripe
+
+## Events Workflow
+
+### Membership
+
+1. checkout.session.completed	    
+  - Store StripeSubscriptionId, UserId, CreatorId, TierId
+  - Save a new Subscription entity with the status "Pending"
+
+2. invoice.payment_succeeded        
+  - Grant access (set Subscription.Active = true or similar)
+  - Record transaction or set StartDate
+  - Notify Creator (e.g., new member)
+
+3. customer.subscription.updated    
+  - Update `EndDate = CancelAt ?? CanceledAt`
+
+4. customer.subscription.deleted	
+  - Revoke access
+  - Mark Subscription as inactive/ended
+
+### Tips
+
+1. checkout.session.completed	    
+  - Store TipId, StripeSessionId, TipperId, CreatorId
+  - PaymentIntentStatus == "paid"
+  - Status = "Paid"
+  - Notify creator
+  - Record transaction