fix mcp accept header

Author: aborruso

LOG.md

@@ -5,6 +5,7 @@
 ### Web GUI chat MVP
 - **Web GUI**: Replaced landing with MCP-backed chat UI (vanilla + Tailwind)
 - **MCP**: Added JSON-RPC search flow with dataset cards
+- **Fix**: Added `Accept` header for MCP 406 requirement
 
 ### Web GUI landing + Pages deploy
 - **Web GUI**: Added static landing page in `web-gui/public`

web-gui/public/index.html

@@ -188,7 +188,10 @@ <h1 class="text-3xl font-semibold">CKAN Open Data Explorer</h1>
         };
         const response = await fetch(endpoint, {
           method: "POST",
-          headers: { "Content-Type": "application/json" },
+          headers: {
+            "Content-Type": "application/json",
+            Accept: "application/json, text/event-stream"
+          },
           body: JSON.stringify(payload)
         });