[SessionService] Implement method that supports writing files

[joao4all]

Prerequisites

• I have written a descriptive issue title
• I have verified that I am running the latest version of the COMET-SDK
• I have searched open and closed issues to ensure it has not already been reported

Description

The SessionService class doesn't provide support for file writing. Implement methods to make it possible.

Suggestion: WriteTransaction should receive a collection of file paths that will be written by the session. With that, it's possible to extend the CreateOrUpdateThings to receive a collection of file paths.

Essentially, the idea here is to implement file upload in the SessionService, allowing users to upload files in the same way they create things in the database.

Steps to Reproduce

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System Configuration

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• COMET version:
  • CDP4Web
• Environment (Operating system, version and so on): Windows
• .NET Framework version: -
• Additional information:

[samatstariongroup]

@joao4all can you make this ticket more explicit and explain what the purpose is?