chore(release): bump engine to v0.5.0

Closes the connector batch 3 release: Azure Blob Storage, BigQuery
(pagination + typed rows), GCP Cloud Run, GitHub Actions, Google Drive,
Google Sheets, HubSpot, Jira, Kafka, Kubernetes, MySQL/MSSQL/Redshift
(with SQL bound parameters), Snowflake (with SQL bound parameters),
Salesforce, Microsoft Entra ID, Microsoft Teams, AWS Bedrock provider
improvements, Stripe, Okta, Shopify, Mailchimp, OneDrive, QuickBooks,
RabbitMQ.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: 2 people

packages/engine/package.json

@@ -1,5 +1,5 @@
 {
   "name": "@mantle/engine",
-  "version": "0.4.0",
+  "version": "0.5.0",
   "private": true
 }