feat: add image optimization task model

internal/services/store.go

@@ -102,6 +102,30 @@ func Migrate(db *sql.DB) error {
 		detail TEXT NOT NULL,
 		created_at TEXT NOT NULL
 	);
+
+	CREATE TABLE IF NOT EXISTS image_tasks (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		source_path TEXT NOT NULL,
+		status TEXT NOT NULL,
+		operation TEXT NOT NULL,
+		duration_ms INTEGER NOT NULL DEFAULT 0,
+		error_message TEXT NOT NULL DEFAULT '',
+		created_at TEXT NOT NULL,
+		updated_at TEXT NOT NULL
+	);
+
+	CREATE TABLE IF NOT EXISTS image_task_results (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		task_id INTEGER NOT NULL,
+		output_path TEXT NOT NULL,
+		before_size INTEGER NOT NULL DEFAULT 0,
+		after_size INTEGER NOT NULL DEFAULT 0,
+		created_at TEXT NOT NULL,
+		FOREIGN KEY(task_id) REFERENCES image_tasks(id)
+	);
+
+	CREATE INDEX IF NOT EXISTS idx_image_tasks_status_created_at ON image_tasks(status, created_at);
+	CREATE INDEX IF NOT EXISTS idx_image_task_results_task_id ON image_task_results(task_id);
 	`)
 	if err != nil {
 		return err