docs: harden navigation, metadata, and deployment checks

[BotshareAI]

Summary

• add intent-first task routes for assembly, software startup, mapping, fault isolation, sensor integration, and customer workflow validation
• generate breadcrumbs, Path chips, sibling navigation, related links, repository ownership, revision dates, feedback, and contact controls at build time
• add page descriptions, JSON-LD, abbreviations, project status, a custom 404, real UI screenshots, and a self-hosted project logo
• add strict generated-link checks and post-deployment root/HTTPS smoke tests
• enable navigation progress and upgrade MkDocs Material

Validation

• mkdocs build --strict passes
• scripts/check_docs.sh passes with 0 warnings
• all 62 index pages have explicit titles
• 26 priority pages have unique descriptions
• generated HTML contains semantic breadcrumbs, related links, owning repository, revision date, feedback link, and JSON-LD

Live finding

The deployed root now serves the new site, so the stale-root issue is resolved. However, http://docs.openamrobot.ai/ currently returns 200 OK instead of redirecting to HTTPS, and HTTPS was not reachable from the audit environment. The post-deploy smoke test intentionally surfaces this until GitHub Pages HTTPS enforcement/custom-domain certificate configuration is corrected.