fix: update test assertions for ON CONFLICT saveNode SQL

Tests expected old INSERT OR REPLACE SQL, updated to match new
INSERT INTO ... ON CONFLICT(node_type) DO UPDATE SET pattern.

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

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

tests/unit/database/node-repository-outputs.test.ts

@@ -56,7 +56,7 @@ describe('NodeRepository - Outputs Handling', () => {
       repository.saveNode(node);
 
       expect(mockDb.prepare).toHaveBeenCalledWith(`
-      INSERT OR REPLACE INTO nodes (
+      INSERT INTO nodes (
         node_type, package_name, display_name, description,
         category, development_style, is_ai_tool, is_trigger,
         is_webhook, is_versioned, is_tool_variant, tool_variant_of,