requesthandler: Add optional context to TriggerHotkeyByName

[exeldro]

Description

Add optional context to TriggerHotkeyByName

Motivation and Context

The same hotkey name can exist on multiple context, to make sure we got the correct one add an optional context

How Has This Been Tested?

Tried calling
{ "requestType": "TriggerHotkeyByName", "requestData": { "hotkeyName": "OBSBasic.SelectScene", "contextName": "Scene 1" } }
Tested OS(s): Windows 11

Types of changes

• New request/event (non-breaking)

Checklist:

• I have read the Contributing Guidelines.
• All commit messages are properly formatted and commits squashed where appropriate.
• My code is not on master or a release/* branch.
• The code has been tested.
• I have included updates to all appropriate documentation.