hearth v0.5.0 - Understanding

Semantic knowledge base. Retrieval now ranks by meaning using local Ollama embeddings (nomic-embed-text), cached per chunk, with automatic fallback to lexical TF-IDF when embeddings are unavailable. kb_add/kb_search use it transparently; the embed model is in the declarative manifest. Everything stays local. Docs: https://ericfinland.github.io/hearth/