perf(strm): 优化 OpenList 元数据下载速度 (#15)

* Add favourite buttons to library list and series detail pages

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Fix favourites list for remote Emby mounted media

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Route favourites to library series detail when appropriate

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Fix favourites link to library series for remote anime paths

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Fix remote Emby playback history and continue watching

- Preserve duration_ms when web player reports duration=0
- Add GET /playback/:id/resume for reliable per-item resume
- Switch home continue watching to /watch-history/continue API
- Set library_id on remote media for play-profile visibility
- Keep continue-watching rows when remote metadata hydration fails

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Fix mobile sort dropdown overflowing off-screen

Align dropdown to button left edge on small screens and cap width
to viewport so sort options stay fully visible on mobile.

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Remove stale Windows binary backup files

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* Fix STRM account edit form not echoing saved config

Return config_preview from account API for server/url/username and
secret flags. Merge partial config updates so empty password/token
fields do not wipe stored credentials.

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

* perf(strm): speed up OpenList metadata downloads with provider-aware concurrency

- Split download semaphore: 115 stays capped at 3 for WAF safety; OpenList/CloudDrive2
  WebDAV metadata uses strm.download_threads (default raised to 6, max 16)
- Scope 115 WAF cooldown to 115 tasks only so OpenList downloads are not paused
- Requeue claimed tasks back to pending when slot acquisition fails or 115 is cooling
- Add tests for separate semaphores and requeue behavior

Co-authored-by: truewhile <truewhile@users.noreply.github.com>

---------

Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: truewhile <truewhile@users.noreply.github.com>

internal/service/playback.go

@@ -13,6 +13,7 @@ import (
 	"time"
 
 	"go.uber.org/zap"
+	"gorm.io/gorm"
 
 	"github.com/ShukeBta/MMTL/internal/model"
 	"github.com/ShukeBta/MMTL/internal/repository"
@@ -47,18 +48,61 @@ func (p *PlaybackService) RecordProgress(ctx context.Context, userID, mediaID st
 	if userID == "" || mediaID == "" {
 		return errors.New("missing user or media")
 	}
-	completed := duration > 0 && position >= duration-30_000
+	dur := p.resolvePlaybackDuration(ctx, userID, mediaID, duration)
+	completed := dur > 0 && position >= dur-30_000
 	h := &model.PlaybackHistory{
 		UserID:     userID,
 		MediaID:    mediaID,
 		PositionMs: position,
-		DurationMs: duration,
+		DurationMs: dur,
 		WatchedAt:  time.Now(),
 		Completed:  completed,
 	}
 	return p.repo.History.Upsert(ctx, h)
 }
 
+// GetProgress returns the saved resume row for one media item, or nil when absent.
+func (p *PlaybackService) GetProgress(ctx context.Context, userID, mediaID string) (*model.PlaybackHistory, error) {
+	if userID == "" || mediaID == "" {
+		return nil, errors.New("missing user or media")
+	}
+	var row model.PlaybackHistory
+	err := p.repo.DB.WithContext(ctx).
+		Where("user_id = ? AND media_id = ?", userID, mediaID).
+		First(&row).Error
+	if errors.Is(err, gorm.ErrRecordNotFound) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &row, nil
+}
+
+func (p *PlaybackService) resolvePlaybackDuration(ctx context.Context, userID, mediaID string, duration int64) int64 {
+	if duration > 0 {
+		return duration
+	}
+	var existing model.PlaybackHistory
+	if err := p.repo.DB.WithContext(ctx).
+		Where("user_id = ? AND media_id = ?", userID, mediaID).
+		First(&existing).Error; err == nil && existing.DurationMs > 0 {
+		return existing.DurationMs
+	}
+	if m, _ := p.repo.Media.FindByID(ctx, mediaID); m != nil && m.DurationSec > 0 {
+		return int64(m.DurationSec) * 1000
+	}
+	if p.remote != nil && IsEmbyRemoteID(mediaID) {
+		mountID, remoteID, _ := DecodeEmbyRemoteID(mediaID)
+		if mount, acct, _ := p.remote.ResolveMount(ctx, mountID); mount != nil && acct != nil {
+			if rm, err := p.remote.RemoteMediaDetail(ctx, mount, acct, remoteID); err == nil && rm != nil && rm.DurationSec > 0 {
+				return int64(rm.DurationSec) * 1000
+			}
+		}
+	}
+	return duration
+}
+
 // HistoryItem joins the playback row with its media so the API consumer
 // gets a fully-populated card without a second round-trip.
 type HistoryItem struct {