Add copy and project note actions for selected text

[touch2be]

Summary

Add a workflow for selected text where the selection is copied immediately, and users can optionally save the selected text as a project note.

Feature request

When a user selects text in OpenGUI:

• The selected text should be copied directly to the clipboard.
• OpenGUI should also offer an additional action to save the selected text as a note for the current project.
• Saving as a note should create or update a Markdown file in the project folder.
• The Markdown file should collect useful information related to the project.

Expected behavior

A possible flow:

1. User selects text in OpenGUI.
2. The selected text is copied automatically.
3. A contextual action appears, for example Save as project note.
4. When selected, OpenGUI writes the text into a project-level Markdown file, for example PROJECT_NOTES.md or .opengui/notes.md.
5. The note entry should preserve enough context to be useful later, such as timestamp, source/session if available, and the selected text.

Why this matters

Users often select important answers, snippets, explanations, decisions, or TODOs while working with agents. Copying is useful for immediate use, but saving the selection as a project note would make OpenGUI better as a long-running project workspace.

Open questions

• Should notes be stored in the project root, for example PROJECT_NOTES.md, or inside a hidden OpenGUI folder, for example .opengui/notes.md?
• Should saving append to one project note file or create separate Markdown files per note?
• Should automatic copy happen for every selection, or only when selecting text inside chat/agent output areas?

Suggested UX

Show a small selection toolbar with actions like:

• Copy
• Save as project note

If automatic copy is enabled, the toolbar can still show confirmation and the optional note action.