Fix governance list input validation

[carrion256]

Summary

Fixes A-066 / Nexus b7898751-488c-4530-a728-d980d83b8a53.

This PR makes the vault/governance list-input policy explicit:

• rejects duplicate Soroban governance config address lists for guardians, allocators, and allowed adapters in the runtime execute_governance application path;
• rejects duplicate supply-queue target_ids at governance submit_set_supply_queue time, before a misleading pending proposal can be queued;
• preserves empty-list semantics where they are already meaningful:
  • guardians and allocators store an empty list (clear effective configured role members),
  • allowed adapters removes the optional adapter binding config,
  • empty supply queue remains an explicit clear/disable-auto-allocation proposal.

Fixed Findings

• A-066 — Nexus b7898751-488c-4530-a728-d980d83b8a53
  • Root cause: list-like governance inputs had mixed implicit behavior: runtime supply queue already rejected duplicates, but governance submission still accepted duplicate supply-queue IDs, and runtime governance config address lists accepted duplicate account/address entries.
  • Fix commit: 26cc9a99719790c634ffedf3c5a86cb96cc816ae
  • Files:
    • contract/vault/soroban/governance/src/lib.rs
    • contract/vault/soroban/governance/src/tests.rs
    • contract/vault/soroban/src/contract/entrypoints.rs
    • contract/vault/soroban/src/tests.rs

Verification

RED evidence observed before fix:

• cargo test -p templar-soroban-runtime test_governance_config_rejects_duplicate_address_lists -- --nocapture
  • failed with duplicate config address list returning Ok(Ok(())) instead of Err(Ok(InvalidInput)).
• cargo test -p templar-soroban-governance submit_set_supply_queue_rejects_duplicate_targets -- --nocapture
  • failed with duplicate supply-queue targets returning Ok(1) instead of Err(InvalidInput).

GREEN verification:

• cargo test -p templar-soroban-runtime test_governance_config_rejects_duplicate_address_lists -- --nocapture
• cargo test -p templar-soroban-runtime test_governance_config_empty_lists_keep_clear_semantics -- --nocapture
• cargo test -p templar-soroban-governance submit_set_supply_queue_rejects_duplicate_targets -- --nocapture
• cargo test -p templar-soroban-governance submit_set_supply_queue_allows_empty_clear_policy -- --nocapture
• cargo test -p templar-soroban-governance cap_action_is_timelocked_and_accepts_after_maturity -- --nocapture
• cargo test -p templar-soroban-runtime --lib -- --nocapture
• cargo test -p templar-soroban-governance -- --nocapture
• just -f contract/vault/soroban/justfile size-budget-check
  • runtime deploy artifact: 93969 bytes (91.77 KiB) <= 131072 bytes
• post-commit hook reran just -f contract/vault/soroban/justfile size-budget-check
  • passed at 93969 bytes

Stack

Base: audit/governance-abi-validation-a056 / PR #442.

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[carrion256]

Superseded by consolidated governance control-plane PR #427. The relevant commits/findings from this PR have been folded into #427 and verified there.

[carrion256]

Closed as superseded by consolidated governance control-plane PR #427.