fix(Jellyfin): Fix cache normalization

[lolo298]

Description

Normalize media search terms before checking the cache to avoid cache miss and duplicate requests.

Acknowledgements

• I read the Activity Guidelines
• I linted the code by running npm run lint
• The PR title follows the repo's commit conventions

Screenshots

Proof showing the creation/modification is working as expected

[dimerp]

🖼️ Activity asset preview

I rummaged through the diff and found these. Finders keepers? No? Fine, they're yours.

Jellyfin (websites/J/Jellyfin) — update

Preview	Source	URL
	logo	https://cdn.rcd.gg/PreMiD/websites/J/Jellyfin/assets/logo.png
	thumbnail	https://cdn.rcd.gg/PreMiD/websites/J/Jellyfin/assets/thumbnail.png

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