Fix bash timeout to properly kill long-running processes

- Use SIGKILL instead of default signal for more forceful termination
- Don't wait for killed processes to avoid hanging
- Add comprehensive test for 120s sleep with 2s timeout
- Timeout now correctly terminates processes within specified time

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: Keno

src/tools/bash.jl

@@ -70,16 +70,26 @@ function execute(tool::BashTool, params::Dict)
         while process_running(process)
             if time() - start_time > timeout_seconds
                 timed_out = true
-                # Kill the process
-                kill(process)
+                # Kill the process forcefully
+                kill(process, Base.SIGKILL)
+                # Give it a brief moment to terminate
+                sleep(0.1)
+                # If still running, force terminate
+                if process_running(process)
+                    try
+                        # Force kill using SIGKILL
+                        kill(process, Base.SIGKILL)
+                    catch
+                        # Process might already be dead
+                    end
+                end
                 break
             end
             sleep(0.1)  # Check every 100ms
         end
 
-        # Wait for process to fully terminate if we killed it
+        # Don't wait for process if we killed it - just return timeout error
         if timed_out
-            wait(process)
             return create_content_response(
                 "Error: Command timed out after $timeout_seconds seconds", 
                 is_error=true

test/test_bash_timeout.jl

@@ -58,4 +58,22 @@
         @test occursin("timed out", result["content"][1]["text"])
         # Note: Output might not be captured due to buffering
     end
+    
+    @testset "Long sleep (120s) with short timeout (2s)" begin
+        # This test ensures that even very long-running commands get cancelled properly
+        # The sleep is for 120 seconds but should be killed after 2 seconds
+        start_time = time()
+        result = execute(tool, Dict(
+            "command" => "sleep 120",
+            "timeout" => 2
+        ))
+        elapsed_time = time() - start_time
+        
+        @test result["isError"]
+        @test occursin("timed out after 2 seconds", result["content"][1]["text"])
+        # The command should be killed within approximately 2 seconds (plus some overhead)
+        # We allow up to 5 seconds total to account for process startup/cleanup overhead
+        @test elapsed_time < 5.0
+        @test elapsed_time >= 2.0
+    end
 end