Initial release.

• CLI (flutter_prerender) that prerenders a flutter build web output to static, crawlable HTML, one file per route.
• Recovers headings, paragraphs, links and image alt text from Flutter's accessibility tree without changing app source.
• Injects <title>, meta description, canonical, Open Graph, Twitter Card and optional JSON-LD per route.
• Generates sitemap.xml.
• Parity guard that compares the generated HTML against Flutter's own accessibility text and warns (or fails, with --fail-on-parity) on injected content.
• Warnings for routes that recover no content (--fail-on-empty to make it fatal) and for routes that duplicate another route's content.
• YAML config file and command-line flags, with flags overriding the file. Invalid numeric flags are rejected instead of silently ignored.