Add SEO/meta updates, JSON-LD schema, hero copy changes, and sitemap

[joelnishanth]

Motivation

• Improve search engine visibility, social previews, and site metadata for the Apply landing page.
• Provide structured data for rich results and FAQ snippets to make the site easier to discover and understand.
• Clarify messaging to emphasize on-device/local AI and privacy-first positioning.

Description

• Updated index.html title, meta tags, Open Graph, and Twitter card data to new messaging and SEO-friendly fields including keywords, author, publisher, and crawler directives.
• Replaced social preview image references with the site monogram and added additional meta fields such as theme-color, application-name, apple-mobile-web-app-title, format-detection, and referrer for improved platform integration.
• Added a script block with JSON-LD structured data describing the Organization, WebSite, WebPage, SoftwareApplication, and an FAQPage to enable rich search results.
• Updated hero copy and badge text in index.html to emphasize on-device AI, local-first behavior, and privacy; added a new sitemap.xml at the project root with the site URL.

Testing

• No automated tests were run for this change.

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Codex Task