Bug 500684

### Why this feature ?
Labels represent an artistic collective or branding under which artists release their work. They often represent a distinct musical identity, bringing together artists with a similar style or vision. 
For users who rely on labels to organize their music, being able to browse music using the "label" id3tag would be a valuable feature.

### Implementation
As a first step, this feature could involve:
- Displaying the Label field in the Metadata and Details views, alongside existing tags like Artist, Album, and Genre.
- Enabling searching by Label, so users can quickly find all tracks associated with a specific label by just typing the label name in the search bar.
In a second phase, a "Label" category could be added to the left-hand navigation panel, listing all labels present in the library, similar to how Genres are displayed.

### Label/Organization vs Publisher
Some music players refer to the label field as "Organization" or "Publisher", but these terms can have different meanings. I would say that "Publisher" typically refers to the company handling distribution, while "Label" or "Organization" represents the branding under which artists release their work, or the record company. Ideally,  both field ( "Label" and "Publisher")  should be available.

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Thank you very much for your time developing this awesome music player ! :)