PR Checklist

Restores the Netlify deployment references that were removed during the Turborepo migration, while keeping outdated Netlify runtime v2 patching out of the current setup.

Closes #

What is the new behavior?

• Restores the root Netlify config for the sanity example deployment.
• Installs and uses @netlify/angular-runtime@4.0.0 for the sanity example SSR handler.
• Pins the Netlify deploy Node version to match the runtime engine requirement.
• Restores the Netlify request fallback used by the currency example when running under the Netlify edge SSR context.
• Restores the public Netlify live-demo links in the Sanity package READMEs.

Does this PR introduce a breaking change?

• Yes
• No

Other information

Validated with:

• volta run --node 22.22.3 --pnpm 11.5.2 pnpm install --frozen-lockfile
• volta run --node 22.22.3 --pnpm 11.5.2 pnpm turbo run build --filter=sanity-example
• volta run --node 22.22.3 --pnpm 11.5.2 pnpm turbo run lint --filter=sanity-example
• Simulated @netlify/angular-runtime onPreBuild/onBuild hooks against the sanity example build output.

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