Task assignment redesign with task templates and task lists

[matayasdurr]

Implemented full task assignment system including:

• Task template CRUD (create, edit, archive)
• Task library UI with search and multi-select
• Task list feature for grouping templates (e.g. Dish Closing)
• Backend logic for managing task lists and templates
• Modals for creating, editing, and managing task lists
• Assignment workflow for both templates and full task lists
• Fixed data model inconsistencies (Description vs Notes, navigation properties)

This improves manager workflow by allowing quick bulk assignment of tasks.