Add complete Stripe billing integration to PodcastItLater

- Implement Biz.PodcastItLater.Billing with checkout sessions, billing
portal, webhook handling - Add subscription database schema: plan_tier,
stripe fields, period dates, stripe_events table - Three-tier pricing:
free (10/month), personal (/month, 50 articles), pro (9/month,
unlimited) - Usage tracking and enforcement with tier-based limits
- Full billing UI with plan display, usage stats, pricing cards,
upgrade buttons - Dashboard shows current tier with billing button -
Update Web.nix with Stripe environment variables - Fix POST redirects
to Stripe with 303 status code for CloudFront compatibility

Amp-Thread-ID:
https://ampcode.com/threads/T-c139e5b5-1901-4cd6-8030-5623bfe1df35
Co-authored-by: Amp <amp@ampcode.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/Biz/PodcastItLater/Web.py b/Biz/PodcastItLater/Web.py
index b5d41dd..6d3cf0a 100644
--- a/Biz/PodcastItLater/Web.py
+++ b/Biz/PodcastItLater/Web.py
@@ -1568,7 +1568,7 @@ def billing_checkout(request: Request, data: FormData) -> Response:
 
     try:
         checkout_url = Billing.create_checkout_session(user_id, tier, BASE_URL)
-        return RedirectResponse(url=checkout_url)
+        return RedirectResponse(url=checkout_url, status_code=303)
     except ValueError as e:
         logger.exception("Checkout error")
         return Response(f"Error: {e!s}", status_code=400)
@@ -1583,7 +1583,7 @@ def billing_portal(request: Request) -> Response:
 
     try:
         portal_url = Billing.create_portal_session(user_id, BASE_URL)
-        return RedirectResponse(url=portal_url)
+        return RedirectResponse(url=portal_url, status_code=303)
     except ValueError as e:
         logger.exception("Portal error")
         return Response(f"Error: {e!s}", status_code=400)