setup frames v2 -> mini apps redirects (base#417)

<!-- start pr-codex -->

## PR-Codex overview
This PR focuses on adding new redirect rules in the `vercel.json`
configuration file to manage the routing of various paths to their
corresponding destinations, enhancing the navigation structure for
users.

### Detailed summary
- Added redirect from `/auth-kit/introduction` to `/auth-kit/`.
- Redirected `/docs/developers/frames` and `/docs/developers/frames/` to
`https://miniapps.farcaster.xyz`.
- Redirected `/developers/frames/v2/getting-started` to
`https://miniapps.farcaster.xyz/docs/getting-started`.
- Redirected `/developers/frames/v2/notifications_webhooks` to
`https://miniapps.farcaster.xyz/docs/guides/notifications`.
- Redirected `/developers/frames/v2/spec` to
`https://miniapps.farcaster.xyz/docs/specification`.

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question}`

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Author: deodad

vercel.json

@@ -56,6 +56,36 @@
       "destination": "https://miniapps.farcaster.xyz/docs/guides/notifications",
       "permanent": true
     },
+    {
+      "source": "/developers/frames/v2/spec",
+      "destination": "https://miniapps.farcaster.xyz/docs/specification",
+      "permanent": true
+    },
+    {
+      "source": "/auth-kit/introduction",
+      "destination": "/auth-kit/",
+      "permanent": true
+    },
+    {
+      "source": "/docs/developers/frames",
+      "destination": "https://miniapps.farcaster.xyz",
+      "permanent": true
+    },
+    {
+      "source": "/docs/developers/frames/",
+      "destination": "https://miniapps.farcaster.xyz",
+      "permanent": true
+    },
+    {
+      "source": "/developers/frames/v2/getting-started",
+      "destination": "https://miniapps.farcaster.xyz/docs/getting-started",
+      "permanent": true
+    },
+    {
+      "source": "/developers/frames/v2/notifications_webhooks",
+      "destination": "https://miniapps.farcaster.xyz/docs/guides/notifications",
+      "permanent": true
+    },
     {
       "source": "/developers/frames/v2/spec",
       "destination": "https://miniapps.farcaster.xyz/docs/specification",