Add OutputIdProof to /api/core/v3/outputs/{outputId}

[Thoralf-M]

https://editor.swagger.io/?url=https://raw.githubusercontent.com/iotaledger/tips/tip48/tips/TIP-0048/openapi3-core.yaml

Started with this, but then wasn't sure about the type for output_commitment_proof

/// The proof of the output identifier.
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
#[cfg_attr(
    feature = "serde",
    derive(serde::Serialize, serde::Deserialize),
    serde(rename_all = "camelCase")
)]
pub struct OutputIdProof {
    /// The slot index of the output.
    slot: SlotIndex,
    /// The index of the output.
    output_index: u16,
    /// The commitment of the transaction that created the output.
    transaction_commitment: SlotCommitmentId,
    /// The proof of the output commitment.
    output_commitment_proof: todo!("what type here?"),
}

Open questions (optional)

Is output_commitment_proof really a string? https://github.com/iotaledger/tips/pull/153/files#r1405938087

[thibault-martinez]

Closed by #1763