* fix: never auto-select embed-only models for chat
Ollama lists nomic-embed-text alongside chat models. Auto-picking
models[0] / recommending the only available id selected the embedder
and every generation failed with HTTP 400 "does not support chat".
- Filter embed-only ids out of GET /v1/models (chat picker)
- Exclude them from /v1/recommended-model; return empty when none left
- Frontend setModels prefers chat models and clears a bad embed selection
- Regression tests for mixed, embed-only, and classifier cases
* fix: harden chat model capability filtering
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Co-authored-by: Elliot Slusky <elliot@slusky.com>
