feat: add Pomodoro timer functionality with logging and project goals

- Implemented Pomodoro timer in the app, allowing users to start, pause, and stop sessions.
- Added context for managing Pomodoro state and actions.
- Integrated time logging for completed sessions to track productivity.
- Enhanced project settings to include time goals and Pomodoro settings.
- Created migration scripts to update the database schema for new project fields and time logs.
- Updated UI components to display Pomodoro controls and project time summaries.
- Added category filtering for projects in the project list view.

backend/app/crud.py

@@ -1,5 +1,7 @@
 from sqlalchemy.orm import Session, joinedload
+from sqlalchemy import func
 from typing import List, Optional
+from datetime import datetime, timedelta
 from . import models, schemas
 
 
@@ -186,3 +188,66 @@ def get_tasks_by_status(db: Session, project_id: int, status: str) -> List[model
         models.Task.project_id == project_id,
         models.Task.status == status
     ).all()
+
+
+# TimeLog CRUD
+def create_time_log(db: Session, task_id: int, time_log: schemas.TimeLogCreate) -> models.TimeLog:
+    db_log = models.TimeLog(
+        task_id=task_id,
+        minutes=time_log.minutes,
+        note=time_log.note,
+        session_type=time_log.session_type,
+    )
+    db.add(db_log)
+    db.commit()
+    db.refresh(db_log)
+    return db_log
+
+
+def get_time_logs_by_task(db: Session, task_id: int) -> List[models.TimeLog]:
+    return db.query(models.TimeLog).filter(
+        models.TimeLog.task_id == task_id
+    ).order_by(models.TimeLog.logged_at.desc()).all()
+
+
+def get_project_time_summary(db: Session, project_id: int) -> dict:
+    """Aggregate time logged across all tasks in a project"""
+    project = get_project(db, project_id)
+
+    # Get all task IDs in this project
+    task_ids = db.query(models.Task.id).filter(
+        models.Task.project_id == project_id
+    ).subquery()
+
+    # Total minutes logged
+    total = db.query(func.sum(models.TimeLog.minutes)).filter(
+        models.TimeLog.task_id.in_(task_ids)
+    ).scalar() or 0
+
+    # Pomodoro minutes
+    pomodoro = db.query(func.sum(models.TimeLog.minutes)).filter(
+        models.TimeLog.task_id.in_(task_ids),
+        models.TimeLog.session_type == "pomodoro"
+    ).scalar() or 0
+
+    # Manual minutes
+    manual = db.query(func.sum(models.TimeLog.minutes)).filter(
+        models.TimeLog.task_id.in_(task_ids),
+        models.TimeLog.session_type == "manual"
+    ).scalar() or 0
+
+    # Weekly minutes (past 7 days)
+    week_ago = datetime.utcnow() - timedelta(days=7)
+    weekly = db.query(func.sum(models.TimeLog.minutes)).filter(
+        models.TimeLog.task_id.in_(task_ids),
+        models.TimeLog.logged_at >= week_ago
+    ).scalar() or 0
+
+    return {
+        "total_minutes": total,
+        "pomodoro_minutes": pomodoro,
+        "manual_minutes": manual,
+        "weekly_minutes": weekly,
+        "weekly_hours_goal": project.weekly_hours_goal if project else None,
+        "total_hours_goal": project.total_hours_goal if project else None,
+    }