Refactor SyncService to Use Centralized Configuration

The SyncService currently contains several hardcoded constants and static configuration values (e.g., file paths, dropped labels, release schedules). To improve maintainability and flexibility, these values should be moved to the central MCP server configuration file at ai/mcp/server/config.mjs.

This ticket covers updating the configuration file and refactoring the SyncService to consume these external values.

Acceptance Criteria

1. The ai/mcp/server/config.mjs file is updated with a new githubWorkflow.issueSync object.
2. This new object contains all configurable aspects of the sync process:
   • issuesDir (absolute path)
   • archiveDir (absolute path)
   • metadataFile (absolute path)
   • droppedLabels (array of strings)
   • releases (array of objects)
3. The SyncService.mjs file is refactored to:
   • Import the aiConfig from ai/mcp/server/config.mjs.
   • Remove the hardcoded path constants (metadataPath, issuesDir, archiveDir).
   • Remove the static config properties (droppedLabels, releases).
   • All methods within the service are updated to reference the values from the imported aiConfig.githubWorkflow.issueSync object instead of local constants or static properties.

Benefits

• Centralized Configuration: All server settings are in one predictable location.
• Improved Maintainability: Business logic (like the release schedule) can be updated without changing the service's code.
• Increased Flexibility: The local file structure can be easily reconfigured for different projects or testing scenarios.
• Cleaner Code: Removes hardcoded values from the service, making the logic itself clearer.