Tree editor island now has 4 tabs: tree, context, validate, render.
The render tab evaluates SX source as live HTML — type a (div (h2 "Hello"))
and see it rendered immediately.
MCP server paths changed from JSON arrays [0,2,1] to SX strings "(0 2 1)".
Fixes serialization issues and is more natural for an SX tool. The
json_to_path function now parses SX via sx-parse.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>