The calendar view code was reorganized so the popover shown for calendar items can be customized more easily, especially for mobile experiences in the enterprise edition. This is an internal cleanup that supports better mobile behavior without changing day-to-day functionality for most users.

This commit move some code to be able to override
Bootstrap popover in web_enterprise for mobile.

Task ID : 2052506

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Odoo Studio now uses the shared field selection records introduced in the core platform. This keeps Studio aligned with the underlying system model and should make future maintenance more consistent without changing day-to-day user workflows.

web_studio: use ir.model.fields.selection

Following odoo/odoo#30228