Struct AppState 

pub struct AppState {
    pub conn: Mutex<Connection>,
    pub embedding_client: Option<Arc<dyn EmbeddingClient>>,
    pub embedding_model: Option<String>,
}

Shared application state passed to all handlers.

Fields

conn: Mutex<Connection>

SQLite connection wrapped in a sync mutex.

embedding_client: Option<Arc<dyn EmbeddingClient>>

Optional async embedding client. When Some, write-path handlers compute an embedding for each new/updated node and /search runs hybrid (FTS + vector) ranking. None short-circuits to FTS-only with no embeddings rows written.

embedding_model: Option<String>

Model name stamped into the embeddings.model column when a client is configured. None is equivalent to no client (no embedding row is written).