Pi harness: serve full outfit depth via /entities endpoint

[koad]

Context

The pi harness at ~/.kingdom/websites/churchofhappy.com/harness/ currently serves outfit as palette-only (hue/sat/brightness from passenger.json). As the outfit schema deepens, the harness should serve the full outfit object and let consumers pick their depth.

Work

• Expand entity-loader.js to read full outfit (once schema is defined)
• Serve outfit at full depth in GET /entities response
• Add optional ?level=N query param for consumers that want a specific LOD
• Avatar serving already works (/entities/:handle/avatar)

Depends on

• Outfit schema: define LOD levels for entity identity capsules #71 (outfit schema definition)

Current state

Harness is built and working (mock provider, SSE streaming, entity loading from ~/./ dirs). Port 20722, KOAD_IO_TYPE=harness-v1.