fix: use PITCH_BASE_URL for short link redirects instead of request.url

Behind Orca's reverse proxy, request.url resolves to http://127.0.0.1:3000
which causes redirects to go to the internal address instead of the public
domain. Use PITCH_BASE_URL (already set in service.toml) as the base.

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

pitch-deck/app/p/[code]/route.ts

@@ -3,6 +3,8 @@ import pool from '@/lib/db'
 
 interface Ctx { params: Promise<{ code: string }> }
 
+const BASE_URL = process.env.PITCH_BASE_URL || 'https://pitch.breakpilot.com'
+
 export async function GET(request: NextRequest, ctx: Ctx) {
   const { code } = await ctx.params
 
@@ -14,8 +16,8 @@ export async function GET(request: NextRequest, ctx: Ctx) {
   )
 
   if (rows.length === 0) {
-    return NextResponse.redirect(new URL('/auth?error=invalid', request.url))
+    return NextResponse.redirect(`${BASE_URL}/auth?error=invalid`)
   }
 
-  return NextResponse.redirect(new URL(`/auth/verify?token=${rows[0].token}`, request.url))
+  return NextResponse.redirect(`${BASE_URL}/auth/verify?token=${rows[0].token}`)
 }