MCP server v0.4.0

• Command-output redaction no longer stalls the server on long token runs.
  160K characters of hex output took 6 s to redact; it now takes milliseconds.
• New EXPRESSIVECSS_MCP_ALLOWED_PROJECT_ROOTS setting limits which
  directories a caller can pass as projectRoot. It is unset by default, which
  keeps the current behavior.
• Calls with a projectRoot are 3 to 5 times faster. The server resolves the
  ExpressiveCSS version once per call and sizes file buffers to the file
  instead of the read limit.
• Tool results use compact JSON text, which is about a third smaller.
• The catalogue, guides and rules cover map, confetti and particles.
• Bundled framework guidance: ExpressiveCSS 0.14.1.