enhancement: add admin bulk hide reviews to handle mass spam

[Naomi-Gift]

hide_review works one review at a time. During a spam attack, an admin would need to call hide_review hundreds of times. A hide_reviews_batch(admin, reviews: Vec<(project_id, reviewer)>) function would allow batch moderation actions in a single transaction, reducing gas cost and admin workload.

[GABRIELOFGOD]

Please assign this to me, I will resolve it

[grantfox-oss]

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Next steps:

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