v1.0.0 of flutter_gemma_rag_qdrant

qdrant-edge on-device RAG vector store for flutter_gemma (native Rust FFI). Opt-in VectorStoreRepository with payload filtering. Native platforms only (no web). Changelog excerpt: - Stable 1.0.0. - Rebuild Android .sowith 16KB page alignment for Android 15 / Play target SDK 35+ (#319; native tag qdrant-edge-v0.7.3).