docs: add v1.3 guide to resources

Author: alpha912

app/docs/page.tsx

@@ -143,6 +143,7 @@ export default function DocsPage() {
             description="Additional learning materials"
             links={[
               { text: 'Specification v1.2 (Latest)', href: 'https://github.com/OmniScriptOSF/omniscript-core/blob/main/spec/v1.2/README.md' },
+              { text: 'v1.3 Features Guide (Latest)', href: '/docs/v1-3-features' },
               { text: 'v1.2 Features Guide', href: '/docs/v1-2-features' },
               { text: 'GitHub Repository', href: 'https://github.com/OmniScriptOSF/omniscript-core' },
               { text: 'Editor Support (Roadmap)', href: 'https://github.com/OmniScriptOSF/omniscript-core/blob/main/spec/roadmap.md' }