fix: update checkout endpoint to accept tier_level from website

Changed endpoint parameters from (priceId, discordId) to just (tier_level).

ISSUE:
Website sends: { tier_level: 1 }
Endpoint expected: { priceId, discordId }
Result: 400 error 'Missing priceId or discordId'

FIX:
- Accept tier_level from request body
- Look up stripe_price_id from stripe_products table
- Determine billing_type (one-time vs subscription)
- Create checkout session without requiring discordId
- Simplified for public checkout flow (no user tracking yet)

SIMPLIFIED CHECKOUT:
- No user verification required
- No Discord linking required
- Stripe collects email during checkout
- Webhook will handle subscription creation later

FILES MODIFIED:
- services/arbiter-3.0/src/routes/stripe.js (45 lines changed)

TESTING:
- Click Subscribe button on website
- Should now create Stripe checkout session successfully
- Should redirect to Stripe payment page

Signed-off-by: Claude (Chronicler #57) <claude@firefrostgaming.com>

services/arbiter-3.0/src/routes/stripe.js

@@ -31,33 +31,24 @@ router.options('/create-checkout-session', cors(corsOptions));
  */
 router.post('/create-checkout-session', cors(corsOptions), async (req, res) => {
   try {
-    const { priceId, discordId } = req.body;
+    const { tier_level } = req.body;
     
-    if (!priceId || !discordId) {
-      return res.status(400).json({ error: 'Missing priceId or discordId' });
+    if (!tier_level) {
+      return res.status(400).json({ error: 'Missing tier_level' });
     }
     
-    // Verify user exists
-    const userResult = await db.query(
-      'SELECT discord_id, username FROM users WHERE discord_id = $1',
-      [discordId]
-    );
-    
-    if (userResult.rows.length === 0) {
-      return res.status(404).json({ error: 'User not found. Please link your Discord account first.' });
-    }
-    
-    // Lookup product to determine billing mode
+    // Get Stripe Price ID from database based on tier level
     const productResult = await db.query(
-      'SELECT tier_level, tier_name, billing_type FROM stripe_products WHERE stripe_price_id = $1',
-      [priceId]
+      'SELECT stripe_price_id, tier_name, billing_type FROM stripe_products WHERE tier_level = $1',
+      [tier_level]
     );
     
     if (productResult.rows.length === 0) {
-      return res.status(400).json({ error: 'Invalid product selected' });
+      return res.status(404).json({ error: 'Invalid tier level' });
     }
     
     const product = productResult.rows[0];
+    const priceId = product.stripe_price_id;
     const billingMode = product.billing_type === 'one-time' ? 'payment' : 'subscription';
     
     // Create Stripe Checkout Session
@@ -65,39 +56,17 @@ router.post('/create-checkout-session', cors(corsOptions), async (req, res) => {
       payment_method_types: ['card'],
       line_items: [{ price: priceId, quantity: 1 }],
       mode: billingMode,
-      success_url: `${process.env.BASE_URL || 'https://discord-bot.firefrostgaming.com'}/checkout/success?session_id={CHECKOUT_SESSION_ID}`,
-      cancel_url: `${process.env.BASE_URL || 'https://discord-bot.firefrostgaming.com'}/checkout/cancel`,
-      client_reference_id: discordId,
-      customer_email: userResult.rows[0].username ? `${userResult.rows[0].username}@firefrost.local` : undefined
+      success_url: 'https://firefrostgaming.com/success',
+      cancel_url: 'https://firefrostgaming.com/subscribe',
+      metadata: {
+        tier_level: tier_level.toString(),
+        tier_name: product.tier_name
+      }
     };
     
-    // Metadata placement differs by mode
-    if (billingMode === 'subscription') {
-      sessionConfig.subscription_data = { 
-        metadata: { 
-          discord_id: discordId,
-          tier_level: product.tier_level.toString()
-        } 
-      };
-    } else {
-      sessionConfig.payment_intent_data = { 
-        metadata: { 
-          discord_id: discordId,
-          tier_level: product.tier_level.toString()
-        } 
-      };
-    }
-    
     const session = await stripe.checkout.sessions.create(sessionConfig);
     
-    // Log checkout creation
-    await db.query(
-      `INSERT INTO admin_audit_log (action_type, target_identifier, details, actor_discord_id)
-       VALUES ('CHECKOUT_CREATED', $1, $2, $3)`,
-      [discordId, JSON.stringify({ tier: product.tier_name, mode: billingMode }), discordId]
-    );
-    
-    res.json({ url: session.url });
+    res.json({ checkout_url: session.url });
     
   } catch (error) {
     console.error('Checkout session error:', error);