Docs for MCP registry CRD

[dmartinol]

Addresses the docs part of #1749

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 48.64%. Comparing base (44aa334) to head (b175127).
⚠️ Report is 12 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2027      +/-   ##
==========================================
- Coverage   48.67%   48.64%   -0.03%     
==========================================
  Files         241      241              
  Lines       30576    30592      +16     
==========================================
  Hits        14882    14882              
- Misses      14574    14590      +16     
  Partials     1120     1120              

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[Copilot]

Pull Request Overview

This PR adds comprehensive documentation for the MCPRegistry CRD, which is an experimental feature for managing MCP server registries in Kubernetes. The documentation covers the architecture, usage patterns, and operational aspects of the registry system.

• Introduces complete MCPRegistry documentation with configuration examples and operational guidance
• Updates existing operator documentation to reference the new registry capabilities
• Provides architectural context and development patterns for the registry feature

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
cmd/thv-operator/REGISTRY.md	Complete MCPRegistry reference documentation covering API, configuration, and troubleshooting
cmd/thv-operator/README.md	Updated operator overview to include MCPRegistry features and installation options
cmd/thv-operator/DESIGN.md	Added architectural decisions and design patterns specific to MCPRegistry
cmd/thv-operator/CLAUDE.md	Developer documentation for MCPRegistry development patterns and testing
README.md	Updated main README to highlight Kubernetes operator capabilities

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[dmartinol]

Note: CI failures will be solved once we merge the e2e test PR which has important changes also tracked in the docs.