feat(wasm): expose presentation verifying key

[sinui0]

This PR exposes the verifying key for a presentation so that it can be checked prior to performing verification.

[0xtsukino]

error[E0599]: no method named `verifying_key` found for struct `tlsn_core::presentation::Presentation` in the current scope
   --> crates/wasm/src/types.rs:248:16
    |
248 |         self.0.verifying_key().into()
    |                ^^^^^^^^^^^^^ method not found in `Presentation`

Actually got a compilation error, I tried to change it to self.0.attestation.body.verifying_key() but then attestation is a private field:

error[E0616]: field `attestation` of struct `tlsn_core::presentation::Presentation` is private
   --> crates/wasm/src/types.rs:248:16
    |
248 |         self.0.attestation.body.verifying_key().into()
    |                ^^^^^^^^^^^ private field

[sinui0]

error[E0599]: no method named `verifying_key` found for struct `tlsn_core::presentation::Presentation` in the current scope
   --> crates/wasm/src/types.rs:248:16
    |
248 |         self.0.verifying_key().into()
    |                ^^^^^^^^^^^^^ method not found in `Presentation`

Actually got a compilation error, I tried to change it to self.0.attestation.body.verifying_key() but then attestation is a private field:

error[E0616]: field `attestation` of struct `tlsn_core::presentation::Presentation` is private
   --> crates/wasm/src/types.rs:248:16
    |
248 |         self.0.attestation.body.verifying_key().into()
    |                ^^^^^^^^^^^ private field

Was this build caching or something?

[sinui0]

tlsn/crates/core/src/presentation.rs

Lines 57 to 60 in 00ed0f9

	/// Returns the verifying key.
	pub fn verifying_key(&self) -> &VerifyingKey {
	self.attestation.verifying_key()
	}

[0xtsukino]

Was this build caching or something?

Ahh i guess it was. i nuked everything and now it builds. Also verified the wasm module locally that it works.