AES-256-GCM encryption (KeyCipher) with master key from NEXUS_MASTER_KEY,
never persisted. ProvidersStore in SQLite: CRUD, enable/disable, default,
encrypted api keys, masked views for UI. KeyResolver applies env>DB precedence
and supports multiple providers. context.ts registers providers dynamically
from resolved config; backward compatible with env-only setups.
Monorepo-lite with shared @nexusai/core and @nexusai/mcp-server (stdio).
Provider-agnostic tools with explicit provider selection; NordRouter adapter
(media generate/poll/download, estimate, upload, models) and search via
perplexity/sonar. Local STT via faster-whisper uv sidecar. SQLite journal of
every generation for usage stats and future admin. 10 MCP tools.