Add WorkflowRun and AlbumEvent repositories with download cancel support

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/claude-agent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

internal/database/album_event_repository.go

@@ -0,0 +1,116 @@
+package database
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+type AlbumEvent struct {
+	ID            string
+	Seq           int64
+	WorkflowRunID string
+	AlbumID       string
+	EventType     string
+	Step          string
+	Message       string
+	DataJSON      []byte
+	CreatedAt     time.Time
+}
+
+type AlbumEventRepository struct {
+	pool *pgxpool.Pool
+}
+
+func NewAlbumEventRepository(pool *pgxpool.Pool) *AlbumEventRepository {
+	return &AlbumEventRepository{pool: pool}
+}
+
+func (r *AlbumEventRepository) Create(ctx context.Context, event *AlbumEvent) error {
+	err := r.pool.QueryRow(ctx,
+		`INSERT INTO album_events (workflow_run_id, album_id, event_type, step, message, data_json)
+		 VALUES ($1, $2, $3, $4, $5, $6)
+		 RETURNING id, seq, created_at`,
+		event.WorkflowRunID, event.AlbumID, event.EventType, event.Step, event.Message, event.DataJSON,
+	).Scan(&event.ID, &event.Seq, &event.CreatedAt)
+	if err != nil {
+		return fmt.Errorf("creating album event: %w", err)
+	}
+	return nil
+}
+
+func (r *AlbumEventRepository) GetByWorkflowRun(ctx context.Context, workflowRunID string) ([]*AlbumEvent, error) {
+	rows, err := r.pool.Query(ctx,
+		`SELECT id, seq, workflow_run_id, album_id, event_type, step, message, data_json, created_at
+		 FROM album_events WHERE workflow_run_id = $1 ORDER BY seq`, workflowRunID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("listing album events by workflow run: %w", err)
+	}
+	defer rows.Close()
+
+	var events []*AlbumEvent
+	for rows.Next() {
+		event := &AlbumEvent{}
+		if err := rows.Scan(&event.ID, &event.Seq, &event.WorkflowRunID, &event.AlbumID, &event.EventType, &event.Step, &event.Message, &event.DataJSON, &event.CreatedAt); err != nil {
+			return nil, fmt.Errorf("scanning album event: %w", err)
+		}
+		events = append(events, event)
+	}
+	return events, nil
+}
+
+func (r *AlbumEventRepository) GetByAlbum(ctx context.Context, albumID string, afterSeq int64, limit int) ([]*AlbumEvent, error) {
+	rows, err := r.pool.Query(ctx,
+		`SELECT id, seq, workflow_run_id, album_id, event_type, step, message, data_json, created_at
+		 FROM album_events WHERE album_id = $1 AND seq > $2 ORDER BY seq LIMIT $3`, albumID, afterSeq, limit,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("listing album events by album: %w", err)
+	}
+	defer rows.Close()
+
+	var events []*AlbumEvent
+	for rows.Next() {
+		event := &AlbumEvent{}
+		if err := rows.Scan(&event.ID, &event.Seq, &event.WorkflowRunID, &event.AlbumID, &event.EventType, &event.Step, &event.Message, &event.DataJSON, &event.CreatedAt); err != nil {
+			return nil, fmt.Errorf("scanning album event: %w", err)
+		}
+		events = append(events, event)
+	}
+	return events, nil
+}
+
+func (r *AlbumEventRepository) GetLatestSeq(ctx context.Context) (int64, error) {
+	var seq int64
+	err := r.pool.QueryRow(ctx,
+		`SELECT COALESCE(MAX(seq), 0) FROM album_events`,
+	).Scan(&seq)
+	if err != nil {
+		return 0, fmt.Errorf("getting latest album event seq: %w", err)
+	}
+	return seq, nil
+}
+
+func (r *AlbumEventRepository) GetAfterSeq(ctx context.Context, afterSeq int64) ([]*AlbumEvent, error) {
+	rows, err := r.pool.Query(ctx,
+		`SELECT id, seq, workflow_run_id, album_id, event_type, step, message, data_json, created_at
+		 FROM album_events WHERE seq > $1 ORDER BY seq LIMIT 1000`, afterSeq,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("listing album events after seq: %w", err)
+	}
+	defer rows.Close()
+
+	var events []*AlbumEvent
+	for rows.Next() {
+		event := &AlbumEvent{}
+		if err := rows.Scan(&event.ID, &event.Seq, &event.WorkflowRunID, &event.AlbumID, &event.EventType, &event.Step, &event.Message, &event.DataJSON, &event.CreatedAt); err != nil {
+			return nil, fmt.Errorf("scanning album event: %w", err)
+		}
+		events = append(events, event)
+	}
+	return events, nil
+}