Add Shared / Reusable Schedules (SQL Agent–Like Scheduling)

Introduce shared / reusable schedule objects that can be referenced by multiple Fabric artifacts (multiple pipelines, notebooks, and other artifacts), similar to SQL Server Agent job schedules. This would allow teams to define execution timing once (for example, a nightly or hourly schedule) and apply it consistently across many workloads, rather than duplicating identical schedules per artifact. Shared schedules would reduce configuration drift, simplify maintenance, and make schedule changes safer and faster by allowing updates in one place. This capability would significantly improve enterprise operations, governance, and migration scenarios for organizations moving from SQL Server Agent–based architectures to Fabric, where coordinated execution timing across many processes is a common requirement.