fix(billing): handle customer.subscription.created webhook + test isolation

- Add customer.subscription.created → subscription.activated mapping in
  stripe.parse_webhook so direct API subscription creation also creates DB rows
- Add customer.subscription.created to setup_stripe.py enabled_events
- Pin PAYMENT_PROVIDER=paddle and STRIPE_WEBHOOK_SECRET="" in test conftest
  so billing tests don't hit real Stripe API when env has Stripe keys
- Add 8 unit tests for stripe.parse_webhook covering all event types

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/padelnomics/billing/stripe.py

@@ -152,6 +152,7 @@ def parse_webhook(payload: bytes) -> dict:
 
     Maps Stripe event types to the shared format used by _handle_webhook_event():
     - checkout.session.completed (mode=subscription) → subscription.activated
+    - customer.subscription.created → subscription.activated
     - customer.subscription.updated → subscription.updated
     - customer.subscription.deleted → subscription.canceled
     - invoice.payment_failed → subscription.past_due
@@ -218,6 +219,23 @@ def parse_webhook(payload: bytes) -> dict:
                 "custom_data": metadata,
             }
 
+    elif stripe_type == "customer.subscription.created":
+        # New subscription — map to subscription.activated so the handler creates the DB row
+        status = _map_stripe_status(obj.get("status", ""))
+        return {
+            "event_type": "subscription.activated",
+            "subscription_id": obj.get("id", ""),
+            "customer_id": str(customer_id),
+            "user_id": user_id,
+            "supplier_id": supplier_id,
+            "plan": plan,
+            "status": status,
+            "current_period_end": _unix_to_iso(obj.get("current_period_end")),
+            "data": obj,
+            "items": _extract_sub_items(obj),
+            "custom_data": metadata,
+        }
+
     elif stripe_type == "customer.subscription.updated":
         status = _map_stripe_status(obj.get("status", ""))
         return {

web/src/padelnomics/scripts/setup_stripe.py

@@ -189,6 +189,7 @@ def create(conn):
     webhook_url = f"{BASE_URL}/billing/webhook/stripe"
     enabled_events = [
         "checkout.session.completed",
+        "customer.subscription.created",
         "customer.subscription.updated",
         "customer.subscription.deleted",
         "invoice.payment_failed",

web/tests/conftest.py

@@ -213,8 +213,10 @@ def patch_config():
     """Set test Paddle config values."""
     original_values = {}
     test_values = {
+        "PAYMENT_PROVIDER": "paddle",  # default to Paddle so mocks work
         "PADDLE_API_KEY": "test_api_key_123",
         "PADDLE_WEBHOOK_SECRET": "whsec_test_secret",
+        "STRIPE_WEBHOOK_SECRET": "",  # no Stripe in default tests
         "RESEND_API_KEY": "",  # never send real emails in tests
         "BASE_URL": "http://localhost:5000",
         "DEBUG": True,

web/tests/test_billing_webhooks.py

@@ -1,5 +1,5 @@
 """
-Integration tests for Paddle webhook handling.
+Integration tests for Paddle webhook handling + Stripe parse_webhook unit tests.
 Covers signature verification, event parsing, subscription lifecycle transitions, and Hypothesis fuzzing.
 """
 import json
@@ -10,6 +10,7 @@ from hypothesis import HealthCheck, given
 from hypothesis import settings as h_settings
 from hypothesis import strategies as st
 from padelnomics.billing.routes import get_subscription
+from padelnomics.billing.stripe import parse_webhook as stripe_parse_webhook
 
 WEBHOOK_PATH = "/billing/webhook/paddle"
 SIG_HEADER = "Paddle-Signature"
@@ -306,3 +307,99 @@ class TestWebhookHypothesis:
             headers={SIG_HEADER: sig, "Content-Type": "application/json"},
         )
         assert response.status_code < 500
+
+
+# ════════════════════════════════════════════════════════════
+# Stripe parse_webhook unit tests
+# ════════════════════════════════════════════════════════════
+
+def _stripe_event(event_type, obj, metadata=None):
+    """Build a minimal Stripe event payload."""
+    if metadata:
+        obj["metadata"] = metadata
+    return json.dumps({"type": event_type, "data": {"object": obj}}).encode()
+
+
+class TestStripeParseWebhook:
+    def test_subscription_created_maps_to_activated(self):
+        payload = _stripe_event(
+            "customer.subscription.created",
+            {"id": "sub_123", "customer": "cus_456", "status": "active", "current_period_end": 1740000000,
+             "items": {"data": [{"price": {"id": "price_abc"}}]}},
+            metadata={"user_id": "42", "plan": "starter"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.activated"
+        assert ev["subscription_id"] == "sub_123"
+        assert ev["customer_id"] == "cus_456"
+        assert ev["user_id"] == "42"
+        assert ev["plan"] == "starter"
+        assert ev["status"] == "active"
+        assert ev["items"] == [{"price": {"id": "price_abc"}}]
+
+    def test_subscription_updated_maps_correctly(self):
+        payload = _stripe_event(
+            "customer.subscription.updated",
+            {"id": "sub_123", "customer": "cus_456", "status": "past_due", "current_period_end": 1740000000,
+             "items": {"data": [{"price": {"id": "price_abc"}}]}},
+            metadata={"user_id": "42", "plan": "pro"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.updated"
+        assert ev["status"] == "past_due"
+
+    def test_subscription_deleted_maps_to_canceled(self):
+        payload = _stripe_event(
+            "customer.subscription.deleted",
+            {"id": "sub_123", "customer": "cus_456", "status": "canceled", "current_period_end": 1740000000,
+             "items": {"data": []}},
+            metadata={"user_id": "42"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.canceled"
+        assert ev["status"] == "cancelled"
+
+    def test_invoice_payment_failed_maps_to_past_due(self):
+        payload = _stripe_event(
+            "invoice.payment_failed",
+            {"subscription": "sub_123", "customer": "cus_456"},
+            metadata={},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.past_due"
+        assert ev["status"] == "past_due"
+
+    def test_checkout_session_subscription_maps_to_activated(self):
+        payload = _stripe_event(
+            "checkout.session.completed",
+            {"mode": "subscription", "subscription": "sub_123", "customer": "cus_456"},
+            metadata={"user_id": "42", "plan": "starter"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.activated"
+        assert ev["subscription_id"] == "sub_123"
+
+    def test_checkout_session_payment_maps_to_transaction(self):
+        payload = _stripe_event(
+            "checkout.session.completed",
+            {"mode": "payment", "customer": "cus_456"},
+            metadata={"user_id": "42"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "transaction.completed"
+
+    def test_unknown_event_returns_empty_type(self):
+        payload = _stripe_event("some.unknown.event", {"customer": "cus_456"})
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == ""
+
+    def test_trialing_status_maps_to_on_trial(self):
+        payload = _stripe_event(
+            "customer.subscription.created",
+            {"id": "sub_123", "customer": "cus_456", "status": "trialing", "current_period_end": 1740000000,
+             "items": {"data": []}},
+            metadata={"user_id": "42"},
+        )
+        ev = stripe_parse_webhook(payload)
+        assert ev["event_type"] == "subscription.activated"
+        assert ev["status"] == "on_trial"