SDD: Implement Persistent Project-Level Tracker Storage & Policies

[moisgobg]

Description

This task redirects the Task Tracker's state from a session-specific temporary directory to a persistent, project-level directory (.gemini/tracker/).

This change ensures that task states are visible, persistent across sessions, and can be committed to Git for better collaboration and tracking.

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Scope of Work

• Configuration Updates
  • Update settingsSchema to include a configurable trackerDirectory property.
• Storage Service Enhancements
  • Modify the Storage service to support path redirection relative to the project root.
  • Implement security checks to ensure paths remain within the project scope.
• Extension Integration
  • Update the built-in sdd extension to use .gemini/tracker as the default directory.
• Policy Adjustments
  • Update sdd.toml policies to always allow tracker_* tools while in Plan Mode.
• Context-Aware Logic
  • Ensure the system only utilizes the custom directory if it exists and the SDD extension is currently active.

[gemini-cli]

Found possible duplicate issues:

• Project-Level State Management with File Locking #22657
• SDD Phase 3: Tasks Integration #23320

If you believe this is not a duplicate, please remove the status/possible-duplicate label.