security: fix silent OT mal OT security

[robinhundt]

The malicious version of the silent OT protocol mistakenly used a semi-honest OT protocol for the base OTs used in silent OT. This commit changes it so that the security of the base OT protocol depends on the chosen security of the silent OT protocol.

[Copilot]

Pull request overview

This PR addresses a critical security vulnerability in the Silent OT implementation where the malicious variant incorrectly used semi-honest security for its base OT protocol. The fix ensures that the base OT security level matches the chosen security level of the Silent OT protocol.

Changes:

• Updated SilentOtSender and SilentOtReceiver to use the generic security parameter S for their base OT extension components
• Removed unnecessary PhantomData<S> fields that are no longer needed since S is now actively used in type parameters
• Removed unused marker::PhantomData import

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
cryprot-ot/src/silent_ot.rs	Changed OT extension components to use generic security parameter S instead of hardcoded SemiHonestMarker; removed PhantomData workaround
cryprot-ot/src/extension.rs	Removed redundant Security trait bound from struct definitions (trait bound likely enforced elsewhere)

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