llama.cpp switches thinking off when reasoning is unset
With assistant.model.parameters.reasoning unset, the llama.cpp provider sends chat_template_kwargs: {"enable_thinking": false, "thinking": false} (create_request in crates/jp_llm/src/provider/llamacpp.rs, around line 232). Request kwargs take precedence over the template's own default and over the server's --chat-template-kwargs, so a model whose template thinks by default (Qwen3, DeepSeek V3.1 and later) stops thinking without anyone having asked it to, and the operator's server-side setting has no effect.
The vLLM provider had the same bug, fixed in c3360b39a ("Leave thinking to the template when unset").
Fix
Send chat_template_kwargs only when reasoning is configured: both kwargs false for off, both true for any effort. With reasoning unset, send neither, so the template and the server decide. reasoning_format: "deepseek" stays, since it only says how the server separates reasoning from the answer.
Test
Request-body tests in llamacpp_tests.rs: no chat_template_kwargs with reasoning unset; both false for off; both true for an effort. The recorded llama.cpp cassettes and compaction snapshots need the kwargs removed from requests that leave reasoning unset.