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/migrate_add_project_goals.py

@@ -0,0 +1,42 @@
+"""
+Migration script to add time goals, category, and pomodoro settings to projects table.
+Run this once if you have an existing database.
+"""
+import sqlite3
+import os
+
+db_path = os.path.join(os.path.dirname(__file__), 'bit.db')
+
+if not os.path.exists(db_path):
+    print("No migration needed - new database will be created with the correct schema.")
+    exit(0)
+
+conn = sqlite3.connect(db_path)
+cursor = conn.cursor()
+
+try:
+    cursor.execute("PRAGMA table_info(projects)")
+    columns = [column[1] for column in cursor.fetchall()]
+
+    new_columns = [
+        ("category", "TEXT DEFAULT NULL"),
+        ("weekly_hours_goal", "INTEGER DEFAULT NULL"),
+        ("total_hours_goal", "INTEGER DEFAULT NULL"),
+        ("pomodoro_work_minutes", "INTEGER DEFAULT 25"),
+        ("pomodoro_break_minutes", "INTEGER DEFAULT 5"),
+    ]
+
+    for col_name, col_def in new_columns:
+        if col_name in columns:
+            print(f"Column '{col_name}' already exists. Skipping.")
+        else:
+            cursor.execute(f"ALTER TABLE projects ADD COLUMN {col_name} {col_def}")
+            print(f"Successfully added '{col_name}'.")
+
+    conn.commit()
+    print("Migration complete.")
+except Exception as e:
+    print(f"Error during migration: {e}")
+    conn.rollback()
+finally:
+    conn.close()