Expose Pre-Meal as an action in Shortcuts #2564

Is your feature request related to a problem? Please describe.
The Shortcuts action "Enable Override Preset" only lists user-defined override presets. The built-in Pre-Meal target can't be selected, so it can't be triggered from a Shortcuts automation (time of day, location, reminder, etc.).

From reading the code: OverrideIntentHandler offers the names stored in overridePresetNames, and LoopDataManager looks the chosen name up in settings.overridePresets. Pre-Meal is stored separately (as the pre-meal correction range override), so it is never offered or matched.

Describe the solution you'd like
Make Pre-Meal available to Shortcuts, either as an extra option in "Enable Override Preset" or as a dedicated "Enable Pre-Meal" action. It should behave like the Pre-Meal button in the app, including being cleared automatically when carbs are logged or when closed loop is turned off.

Describe alternatives you've considered

• Creating a custom override preset with the same target range. It works, but it isn't cleared when carbs are logged, so it needs a fixed duration. It also replaces any override that is already active.
• A Shortcuts notification or reminder at meal time, then starting Pre-Meal by hand in the app.

Additional context

• Loop version : 3.14.8
• iOS version: 27.0.1
• Tested in the Shortcuts app: Pre-Meal does not appear in the preset picker; my custom activity presets do.