Add transferWorkflow diff operation to move workflows between n8n projects:
- TransferWorkflowOperation type with destinationProjectId field
- WorkflowDiffEngine validates and tracks transfer intent
- Handler calls PUT /workflows/{id}/transfer after update
- N8nApiClient.transferWorkflow() method
- Zod schema validates destinationProjectId is non-empty
- Tool description and documentation updated
- inferIntentFromOperations case for transfer
Also fixes two pre-existing bugs found during review:
- continueOnError path now properly extracts/propagates activation flags
- Debug log in updateConnectionReferences shows correct old name
Based on work by @djakielski in PR #645.
Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en
