Inject memories into a conversation

Returns the selected memories plus inject_text, a ready-to-paste block that tells the model to cite each memory by its #N. Fee: 0.1 AIC (half burned, half to treasury). Quarantined and archived memories are skipped silently. With optimistic: true the response comes back immediately and the payment settles in the background: poll /v1/inject/status/{id} with payment.inject_log_id. Sealed memories come back as ciphertext (content_blob, scheme 2) and as a placeholder inside inject_text; the client decrypts them.