Wire the REPL to a local Ollama instance via streaming HTTP (SSE).
LLMClient handles async streaming chat, StreamHandler renders live
Markdown via Rich and accumulates tool call fragments. Startup now
runs a preflight check that verifies Ollama is reachable and the
configured model is pulled, exiting with a clear message on failure.
Also adds .gitignore and updates config to use qwen3.5.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>