[19.0][ADD] project_task_planning

[angelmoya]

Description

This PR introduces a new module to enhance project task management by adding detailed resource allocations and time-cycle workload planning.

It provides managers with a structured workflow to transition from general task estimation to precise employee scheduling, ensuring clear visibility over team capacity and availability.

Key Features

• Multi-Employee Allocations: Allows creating one or multiple resource allocations within a single task, each with independent start/end dates and allocated hours.
• Allocation Control: Adds a control mechanism to track and balance the difference between the task's Estimated Hours and the total Allocated Hours.
• Cycle-Based Planning: Once an allocation is set, users can generate planning timelines based on configurable cycles (Days, Weeks, Months) within the allocation's timeframe.
• Workload & Availability Tracking: Enables manual distribution of hours across time buckets to monitor employee capacity, planned hours, and real-time availability.

Technical Specifications

• Added new models for Task Allocations and Planning Buckets/Cycles.
• Implemented constraints to ensure allocation dates fall within the task's timeframe.
• Added compute fields for checking estimated vs. allocated hours variance.

How to test / Steps to reproduce

1. Go to Project and open/create a Task with a Start and End Date.
2. In the Allocations tab, add an employee line, define their specific dates, and assign a number of hours.
3. Verify that the task-level control correctly reflects the difference between the task's Estimated Hours and your Allocated Hours.
4. Save the allocation and generate/configure the planning cycles (Days, Weeks, or Months).
5. Input hours into the generated time buckets and verify that the employee's workload and availability update accordingly.