[validate-docs] ♻️ group Validate pages under /validate and rename connection guides

[msanyam]

Summary

Groups all Validate documentation under /validate/ and renames the connection guides to three parallel pages: Using MCP, Using Postman, Using curl. This makes room for Simulate as a sibling section later without moving Validate again. Stacked on #10.

Changes

• Move guides/* and api/* under validate/ (git mv, history preserved)
• Rename guides/quickstart → validate/using-curl and guides/mcp-integration → validate/using-mcp; update titles and H1s
• Rewrite validate/index.md (formerly guides/index.md) as the Validate overview: Get started / Choose how to connect / Go further
• config.md: top nav becomes Overview · Validate · API Reference (Validate REST API, Validate MCP Tools) · Support; sidebar scoped to /validate/
• Fix all internal links to the new paths; "Quickstart" link text → "Using curl"
• Add src/pages/redirects.json (EDS sheet format, 27 entries) mapping old /guides/* and /api/* URLs to /validate/*
• No body-content changes beyond links and titles

Old	New
guides/index.md	validate/index.md
guides/quickstart/	validate/using-curl/
guides/mcp-integration/	validate/using-mcp/
guides/using-postman/	validate/using-postman/
guides/{authentication,core-concepts,review-feedback}/	validate/…
api/index.md	validate/api/rest/index.md
api/mcp/index.md	validate/api/mcp/index.md

Testing

• npm run lint: 11 files, 0 issues
• Script check that every relative and config.md link resolves to an existing file: 0 broken
• Not verified: rendered nav/sidebar and redirect behaviour (needs a stage deploy). redirects.json gives client-side redirects only; server-side (Fastly) redirects need a devsite-team request.
• contributors.json still lists old paths; it is regenerated by the existing manual workflow.

[github-actions]

🔍 Linter Report

Click to expand full report

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                     LINTER REPORT
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Generated: 2026-10-06T03:52:17.479Z
Mode: Full Linting (all rules + dead links check)
Target Directory: /home/runner/work/abi-docs/abi-docs

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Files to process: 11


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                        SUMMARY
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  📁 Files processed:    11
  📄 Files with issues:  0
  ❌ Total errors:       0
  ⚠️  Total warnings:     0
  📋 Total issues:       0

Result: ✅ PASSED - All files passed linting successfully!

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