Function analyze_task_structure_background 

pub fn analyze_task_structure_background(pool: SqlitePool)

Analyze task structure in background and store suggestions

This function runs asynchronously without blocking the caller. Suggestions are stored in the database and shown at next interaction.

Rate Limiting: Uses a cooldown period (default 5 minutes) to prevent unlimited task spawning. If called within the cooldown period, it’s a no-op.