Documentation changelog

Significant public changes to Nava's Developer Preview documentation. This is a docs changelog, not a product-availability commitment.

SDK-first and MCP-first Guardian integration

• Added top-level Nava SDK guides and copyable prompts for configuration, MCP, TypeScript, and the bundled agent skill.
• Moved direct Guardian REST usage into an advanced path and routed previous SDK and MCP URLs into the top-level SDK section.
• Strengthened Gateway and NavaClaw prompts, clarified the audit-only prompt field, and replaced the generic AI page handoff.

Interactive Developer Preview documentation

• Added generated OpenAPI references for Nava Guardian and Nava Gateway.
• Added policy-check, verdict-handling, and payment-flow explorers that run entirely in the browser.
• Connected guide snippets to runnable examples and added copyable prompts for agent-assisted integration.