fix: Fusion strip stream_options + reasoning model test probe

- combos: strip stream_options from Fusion panel fan-out to avoid DeepSeek 400 (#3024)
- dashboard: raise model-test probe budget to 1024 + soft-pass reasoning-only responses (#3010)

open-sse/services/combo.js

@@ -530,7 +530,10 @@ export async function handleFusionChat({ body, models, handleSingleModel, log, c
   log.info("FUSION", `Combo "${comboName}" | panel=${panel.length} [${panel.join(", ")}] | judge=${judge} | quorum=${minPanel}`);
 
   // 1. Fan out to the panel in parallel: non-streaming, tools stripped (we want prose).
-  const { tools, tool_choice, ...rest } = body;
+  const { tools, tool_choice, stream_options, ...rest } = body;
+  // Fusion runs panel models non-streaming; drop stream_options too, or providers
+  // like DeepSeek reject it with "stream_options should be set along with stream = true".
+  // See issue #3024.
   const panelBody = { ...rest, stream: false };
 
   // Flatten tool turns to prose so panel models keep context without emitting tool_calls.