Sync OpenMetadata Standards with 2.0.0

[harshach]

Summary

• sync all 911 JSON schemas from the official OpenMetadata 2.0.0-release tag at 6861999f
• document the full schema delta: 98 added, 135 modified, and 3 removed versus the current Standards snapshot; 86 added, 107 modified, and 3 removed versus 1.13.4-release
• add a complete 1.13 → 2.0 migration guide covering API contracts, search, collaboration, governance, data quality, lineage, ingestion, applications, platform/security, and UI customization
• bump the package, documentation, and ontology version to 2.0.0 and refresh schema/connector counts
• extend the ontology, SHACL shapes, and JSON-LD contexts for AI governance, Context Center, Tasks, Announcements, Activity Stream, attachments, and intake forms

Source

• Release: https://github.com/open-metadata/OpenMetadata/releases/tag/2.0.0-release
• Source commit: open-metadata/OpenMetadata@6861999
• Release comparison: open-metadata/OpenMetadata@1.13.4-release...2.0.0-release

Validation

• schema tree is byte-for-byte identical to the upstream 2.0.0 release source
• all 911 schemas parse as JSON and all 5,959 local $ref targets resolve
• all Turtle files parse; ontology validation conforms to the SHACL graph
• all 17 JSON-LD contexts parse, and every term in the new/extended 2.0 contexts is declared in the ontology
• internal Markdown links pass and MkDocs completes a production build
• git diff --check passes