Add MCP Server configuration reference

[michaellwest]

Scope

Full configuration reference for appsettings.json:

• Instances (multi-instance setup, auth types)
• Security mode selection
• Rate limiting (MaxConcurrentExecutions, MaxExecutionsPerMinute, MaxScriptSizeBytes)
• Resilience (retry, circuit breaker, timeouts)
• Audit logging (enable, retention, rotation)
• Media limits
• Environment variable resolution (env: prefix)
• Example configurations for common scenarios

References

• SitecorePowerShell/mcp-server (Configuration/ directory, appsettings.json)

Files

• New mcp-server/configuration.md
• SUMMARY.md — Add under MCP Server