feat: Segregate PRDs and Tasks by Project Using a YAML Field

[orakemu]

Motivation

Mixing tasks from different features or projects leads to clutter and confusion. Grouping by project (in metadata) improves organization, status tracking, and reporting.

Proposed Solution

• Add a project field to the YAML metadata of every task, subtask, and PRD.
• All project grouping, filtering, and reporting is performed by reading this field—files can remain in a flat structure.
• Update commands and UI (if present) to support filtering/grouping by project.

High-Level Workflow

1. Update YAML schema to include project field.
2. Refactor commands that list or filter tasks to use project metadata.
3. Update documentation and usage examples.
4. Optionally, provide a project summary/report command.

Key Elements

• project: field in YAML
• Grouping/filtering logic in CLI and/or UI
• Flat file structure (no project folders)

Example Workflow

$ task-master list-tasks --project Authentication
→ [shows only Authentication tasks]

Implementation Considerations

• depends on issue #707
• Consistent project naming to avoid duplicates
• Retrofitting existing tasks with project metadata
• Backward compatibility for legacy tasks

Out of Scope (Future Considerations)

• Project/feature dependencies or hierarchies
• Project-level dashboards

[eyaltoledano]

This is a planned improvement (I'm open to PRs) #76 (which could be extended to projects as well as milestones)