[Security Solution][Notes] - add toggle to management page to hide notes on unsaved timelines

[PhilippeOberti]

Description

In 8.15 we added a new notes functionality, including a notes management page to allow users to quickly delete notes.

Recently, @paulewing discovered that if a user investigate an alert generated by a rule that has an investigation guide, we create a note behind the scene. https://github.com/user-attachments/assets/827720c4-4115-487b-9e6f-02658dff5b28

Despite the fact that this might be a big problem on customer's environments and we might need to look into how to clean these up, we should add a toggle on the notes management page to hide all of these notes related to unsaved timelines. This would allow users to hide them entirely, or show only these to be able to bulk delete them.

Here are the mocks for the notes management page: https://www.figma.com/design/Chimc9hK29zXGCrMBb5frH/%5B8.%2B%5D--Comments-in-document-%2B-Timeline?node-id=5441-96903&node-type=canvas&t=RuMVNn9IPZ9JFhCJ-0 but no UI has been decided on the toggle functionality. We might be able leverage/use the Tags dropdown in the mocks above.

It seems that a dropdown might the most flexible, showing the following options:

• show all notes
• show notes created without a timeline
• show notes created with a saved timeline
• show notes created with an unsaved timeline

Acceptance criteria

• add a toggle on the notes management page to allow users to select different types of notes

[elasticmachine]

Pinging @elastic/security-threat-hunting-investigations (Team:Threat Hunting:Investigations)

[elasticmachine]

Pinging @elastic/security-solution (Team: SecuritySolution)