* Improve README with mermaid diagram and structured sections
Replace static architecture diagram with maintainable mermaid flowchart showing the multiplexer architecture. Add structured sections for Overview, Features, Configuration, Testing, and Troubleshooting to better explain the extension's purpose and usage.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
* Simplify mermaid diagram for better readability
Replace complex nested subgraphs with a simple, clear flowchart that matches the clarity of the original static diagram. Add note about subscription ID rewriting feature.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
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Co-authored-by: Claude <noreply@anthropic.com>
