Feature/import export events

[brandochn]

This pull request adds robust support for exporting and importing profiler events in JSON format within the WinForms application. It introduces a new service for event serialization, integrates export/import functionality into the UI, and ensures that event data is correctly extracted and restored to/from the grid. The changes improve usability by allowing users to save and reload profiling sessions, and they handle errors gracefully throughout the process.

Event Export/Import Functionality:

• Added EventExportImportService to handle exporting events to JSON and importing them back, preserving row order and extracting column names while excluding metadata fields.
• Implemented OnExportEvents and OnImportEvents handlers in MainPresenter to support exporting the current grid data to a JSON file and importing events from a JSON file, including dynamic column creation and error handling.

UI Integration:

• Added "Export Events..." and "Import Events..." options to the File menu in the main view, and wired them to the new event handlers. [1] [2]
• Updated the IMainView interface and its implementation to support new export/import events. [1] [2]

Data Extraction Helper:

• Introduced DataGridViewHelper for extracting event data from DataGridView rows and columns, ensuring consistent serialization for export.

Wiring and Presenter Updates:

• Registered the new export/import event handlers in the MainPresenter constructor and ensured grid state is managed correctly during import. [1] [2]