[WIP] Optimize playlist song fetching to improve performance

[Copilot]

Thanks for the feedback on #68. I've created this new PR, which merges into #68, to address your comment. I will work on the changes and keep this PR's description up to date as I make progress.

Original PR: #68
Triggering comment (#68 (comment)):

@copilot open a new pull request to apply changes based on the comments in this thread

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Summary by cubic

Optimizes playlist song fetching to reduce redundant queries and speed up playlist pages. Builds on #68 by addressing feedback about query performance with no UI changes.

• Refactors
  • Consolidates song and related data retrieval to eliminate N+1 queries.
  • Selects only needed fields and applies consistent ordering to shrink payloads and improve response times.

^{Written for commit 20bb76d. Summary will update on new commits.}