Replace status_id with in_progress boolean field

- Remove task_statuses lookup table and StatusID foreign key
- Add InProgress boolean field to Task model
- Add database migration (005_replace_status_with_in_progress)
- Update all handlers, services, and repositories
- Update admin frontend to display in_progress as checkbox/boolean
- Remove Task Statuses tab from admin lookups page
- Update tests to use InProgress instead of StatusID
- Task categorization now uses InProgress for kanban column assignment

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

internal/database/database.go

@@ -114,7 +114,6 @@ func Migrate() error {
 		&models.TaskCategory{},
 		&models.TaskPriority{},
 		&models.TaskFrequency{},
-		&models.TaskStatus{},
 		&models.ContractorSpecialty{},
 		&models.TaskTemplate{}, // Task templates reference category and frequency