feat(strm): 同名多版本择优 / keep_ext，并支持合并展示与播放切换 (#30)

* feat(strm): 同名多版本择优/keep_ext，并支持合并展示与播放切换

默认对同名不同扩展（如 .mkv/.mp4）按体积→mtime→扩展名优先级择优生成一条 strm，冲突打日志；开启 keep_ext 则分别生成 name.ext.strm。媒体详情与播放器可切换版本，列表继续合并同片多版本，Emby MediaSources 名称区分容器/分辨率。

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

* fix(meta): 边车匹配忽略 .mkv.strm 中间扩展，同片共享 NFO/海报/字幕

NFO、海报、字幕与刮削写出统一使用 mediaSidecarBase 词干，使竞女01.mkv.strm
与竞女01.mp4.strm 配对同一套 竞女01.nfo / 竞女01-poster / 竞女01.srt；
仍兼容历史上的 name.mkv.nfo 命名。

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

* fix(emby): People NFO 按共享词干匹配 keep_ext strm

resolveMediaPeople 改为查找竞女01.nfo（并兼容旧的竞女01.mkv.nfo），
同时修正把 decodeNFOFile 的 partial 误当 ok 导致完整 NFO 被跳过的问题。

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

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

internal/service/emby_items_detail.go

@@ -538,21 +538,35 @@ func (e *EmbyService) resolveMediaPeople(ctx context.Context, m *model.Media) []
 		return []map[string]any{}
 	}
 	dir := filepath.Dir(m.Path)
-	ext := filepath.Ext(m.Path)
-	base := strings.TrimSuffix(m.Path, ext)
-	candidates := []string{
-		base + ".nfo",
-		filepath.Join(dir, "movie.nfo"),
-		filepath.Join(dir, "tvshow.nfo"),
+	candidates := make([]string, 0, 6)
+	seenPath := map[string]struct{}{}
+	add := func(path string) {
+		path = strings.TrimSpace(path)
+		if path == "" {
+			return
+		}
+		key := strings.ToLower(filepath.Clean(path))
+		if _, ok := seenPath[key]; ok {
+			return
+		}
+		seenPath[key] = struct{}{}
+		candidates = append(candidates, path)
 	}
+	// 共享词干优先（竞女01.mkv.strm → 竞女01.nfo），并兼容旧的单层剥扩展命名。
+	add(nfoPath(m.Path))
+	for _, base := range mediaSidecarBaseVariants(m.Path) {
+		add(filepath.Join(dir, base+".nfo"))
+	}
+	add(filepath.Join(dir, "movie.nfo"))
+	add(filepath.Join(dir, "tvshow.nfo"))
 
 	people := make([]map[string]any, 0)
 	seen := make(map[string]bool)
 
 	for _, p := range candidates {
 		if fi, err := os.Stat(p); err == nil && !fi.IsDir() {
-			doc, ok, err := decodeNFOFile(p)
-			if err == nil && ok && doc != nil {
+			doc, _, err := decodeNFOFile(p)
+			if err == nil && doc != nil {
 				for _, d := range doc.Directors {
 					name := strings.TrimSpace(d)
 					if name == "" {