Summary

Expose personality presets via REST API so clients can discover available presets without hardcoding names.

Motivation

Currently, preset names must be known in advance -- there's no API to list or inspect available presets. The setup wizard silently falls back to pragmatic_builder for unknown presets. Clients (dashboard, CLI, third-party integrations) need a way to discover what's available.

Proposed Endpoints

• GET /api/v1/personalities/presets -- list all available presets (name, description, traits summary)
• GET /api/v1/personalities/presets/{name} -- get full preset definition (all fields)
• GET /api/v1/personalities/schema -- return the PersonalityConfig JSON schema (for client-side validation)

Current State

• PERSONALITY_PRESETS is a frozen MappingProxyType in src/synthorg/templates/presets.py
• get_personality_preset(name) exists but is internal-only (not exposed via API)
• Templates already support both personality_preset (by name) and personality (inline dict)
• PersonalityConfig model in src/synthorg/core/agent.py validates all personality data

Notes

• Read-only endpoints for builtin presets; CRUD for user-defined presets is tracked separately
• Should include pagination for future-proofing as custom presets are added
• Response should distinguish builtin vs user-defined presets (via a source field)