fix: handle tool calls in streaming mode - fall back to non-streaming

Model says "let me research" then calls web_search tool.
Streaming path ignored tool_calls entirely (no-op comment).
Now: detect tool_calls delta, cancel stream, fall back to non-streaming
which properly executes tools and returns results.

src/bot/index.js

@@ -379,10 +379,11 @@ export async function initBot(config, api, tools, skills, agents) {
                 fullResponse += content;
                 onDelta(content);
               }
-              // Check for tool calls in streaming
+              // Tool calls in streaming - abort stream, fall back to non-streaming (handles tools)
               if (delta.tool_calls) {
-                // Tool calls in streaming mode — accumulate and handle after stream
-                // For now, fall through to non-streaming tool handling
+                logger.info("Tool call in stream, falling back to non-streaming");
+                reader.cancel().catch(() => {});
+                return await chatWithAI(body.messages, { maxTokens: body.max_tokens });
               }
             }
           } catch {