Add an option to show notification when copying content

# Description of the new feature/enhancement

We want to see a box that says "Copied" when we copy a text inside a Terminal window. For example, if we highlighted a text called "C:\Windows\System32" while running Command Prompt inside a Terminal window, the dialog box would say "Copied".

# Proposed technical implementation details (optional)

Add "Show notification when copying content" in Terminal Settings->Interaction.

Start by tracing the Terminal Settings > Interaction area and the existing copy-content handling. Done means an optional setting controls whether a "Copied" notification appears after text is copied inside a Terminal window.

Written by the indexing model from the issue text.