Propagate nested agent approval interruptions through tool pipeline

Signed-off-by: Bryan Frimin <bryan@getprobo.com>

pkg/agent/errors.go

@@ -42,12 +42,37 @@ type (
 		Messages         []llm.Message
 		Usage            llm.Usage
 		Turns            int
+
+		outerState *outerLoopState
 	}
 
 	needsApprovalError struct {
 		allToolCalls     []llm.ToolCall
 		pendingApprovals []llm.ToolCall
 	}
+
+	nestedInterruptionError struct {
+		inner          *InterruptedError
+		toolCallID     string
+		allToolCalls   []llm.ToolCall
+		completedCalls []completedCall
+	}
+
+	outerLoopState struct {
+		agent          *Agent
+		messages       []llm.Message
+		usage          llm.Usage
+		turns          int
+		allToolCalls   []llm.ToolCall
+		toolCallID     string
+		completedCalls []completedCall
+		innerInterrupt *InterruptedError
+	}
+
+	completedCall struct {
+		toolCallID string
+		result     ToolResult
+	}
 )
 
 func (e *MaxTurnsExceededError) Error() string {
@@ -69,3 +94,7 @@ func (e *InterruptedError) Error() string {
 func (e *needsApprovalError) Error() string {
 	return fmt.Sprintf("%d tool call(s) require approval", len(e.pendingApprovals))
 }
+
+func (e *nestedInterruptionError) Error() string {
+	return fmt.Sprintf("nested agent interrupted: %s", e.inner.Error())
+}