Function compute_shielded_identity_balance_write_fee 

pub fn compute_shielded_identity_balance_write_fee(
    num_actions: usize,
    platform_version: &PlatformVersion,
) -> Result<Credits, ProtocolError>

Computes the conservative admission floor (in credits) for ShieldFromIdentity: compute_minimum_shielded_fee plus the versioned per-action and flat identity-write allowances, priced at the per-byte storage rate. The allowances cover the complete execution-event admission estimate, including the estimated note/nullifier and identity writes and the validation context.

The transition’s authoritative fee is metered at execution; this floor stands in for it where state is not yet available, so that an identity that could not pay the complete fee is refused before the expensive Orchard proof verification runs. It is also the client-side estimate of the total fee.

Dispatches on the SAME version key (dpp.methods.compute_minimum_shielded_fee) as compute_minimum_shielded_fee so the formulas evolve together across protocol versions.

Parameters

• num_actions: number of Orchard actions in the bundle
• platform_version: protocol version (determines the formula version and fee constants)