blifi: BLE-based Wi-Fi provisioning for ESP32. Provision Wi-Fi credentials over an encrypted BLE session (X25519 + AES-256-GCM, gated by a Proof-of-Possession) instead of a hotspot/captive portal. Includes a NimBLE GATT transport, Wi-Fi station manager with NVS persistence and retry/backoff, and an optional reset-pin factory reset. Companion Flutter package: `blifi` on pub.dev.