Fix R128 and remaining ID fields to accept both JSON types

- Track.R128 and TrackShort.R128: float64 → JSONR128 (accepts both JSON number and object)
- All remaining primary ID fields: string → JSONID (accepts both JSON string and number)
  Fixed in: account, artist, clip, concert, feed, label, landing, metatag,
  music_history, pin, queue, radio, search, settings, supplement

internal/models/track_short.go

@@ -8,7 +8,7 @@ import (
 // TrackShort represents a lightweight track used in lists.
 type TrackShort struct {
 	BaseModel
-	ID                       string            `json:"id"`
+	ID                       JSONID            `json:"id"`
 	Title                    string            `json:"title"`
 	DurationMs               int               `json:"duration_ms"`
 	StorageID                string            `json:"storage_id"`
@@ -20,7 +20,7 @@ type TrackShort struct {
 	Explicit                 bool              `json:"explicit"`
 	Available                bool              `json:"available"`
 	AvailableForPremiumUsers bool              `json:"available_for_premium_users"`
-	R128                     float64           `json:"r128"`
+	R128                     JSONR128          `json:"r128"`
 	TrackSharingFlag         string            `json:"track_sharing_flag"`
 	Major                    *Major            `json:"major"`
 	Lyrics                   *SupplementLyrics `json:"lyrics"`