docs(stripe-integration): add README documentation

Add Stripe integration README file to the component registry, making it
available as docs/STRIPE-README.md for users of the integration.

Author: wschenk

components/stripe-integration/component.json

@@ -15,6 +15,11 @@
     "https://registry.thefocus.ai/r/cli-component.json"
   ],
   "files": [
+    {
+      "path": "components/stripe-integration/README.md",
+      "type": "registry:file",
+      "target": "docs/STRIPE-README.md"
+    },
     {
       "path": "components/stripe-integration/app/page.tsx",
       "type": "registry:file",