Documentation Landing Page Refinement

Docs Landing Page

Revised the hero copy on docs.speybooks.com to better reflect the documentation site’s purpose as a wayfinding page rather than a marketing surface.

• New headline — “Deterministic accounting, specified as an API.” replaces the previous title, avoiding repetition of the brand name already present in the logo.
• Constraint-style subtitle — “Schema-validated. Versioned. Formally ordered.” Three declarative statements that read like a spec header, not a sales pitch.
• Stats badge — resource and endpoint counts now display in a pill badge below the search bar, matching the visual language used on the features page.
• Tightened vertical rhythm — reduced spacing between headline and subtitle, increased spacing before the search bar, creating a clearer separation between the statement block and the search tool.
• Removed redundant copy — the previous trust line and monospace stats line replaced by the single badge, reducing visual noise around the search bar.

All changes apply to both light and dark themes. Badge tokens follow the existing design token system with no raw hex values.