fix: use the base fee for VaultCreate autofill

[kuan121]

High Level Overview of Change

autofill now gives VaultCreate the network base fee instead of one owner reserve.

Jira: DGE-8227

Context of Change

_calculate_fee_per_transaction_type treated VaultCreate like AccountDelete and AMMCreate, and charged it reserve_inc: 0.2 XRP on Mainnet, compared with a base fee of 10 drops. rippled stopped charging VaultCreate an owner reserve in 3.2.0 (XRPLF/rippled#5954). Today only AccountDelete and AMMCreate override calculateBaseFee with calculateOwnerReserveFee. So every autofilled VaultCreate overpaid by about 2 XRP, which is destroyed with the fee.

The owner-reserve fee for VaultCreate dates from #814, which added Single Asset Vault support. xrpl.js had the same overcharge and fixed it in XRPLF/xrpl.js#3430. This PR makes the same change here.

Type of Change

• Bug fix (non-breaking change which fixes an issue)

There is one side effect for callers who set VaultCreate.fee to the old 2 XRP by hand and submit with check_fee=True. _check_fee now treats that fee like any other ordinary transaction's: it is higher than both the calculated fee and the 0.1 XRP ceiling, so it is refused as too high.

Did you update CHANGELOG.md?

• Yes

Test Plan

• Unit tests in the new tests/unit/asyn/transaction/test_owner_reserve_fee.py:
  • VaultCreate pays the base fee.
  • AccountDelete and AMMCreate still pay the owner reserve.
  • The VaultCreate test fails on main and passes with the fix.
• Integration tests: all autofill VaultCreate, which now pays the base fee, and rippled accepts it. They ran against rippleci/xrpld:develop --standalone (xrpld 3.4.0-rc1):
  • the single-asset vault, vault_info, lending and lending V1_1 suites
  • the fee tests in sugar/test_transaction.py
• Other tests: the full unit suite, flake8 and mypy --strict pass.

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📥 Commits

Reviewing files that changed from the base of the PR and between 7a81134 and e46a9c6.

📒 Files selected for processing (3)

• CHANGELOG.md
• tests/unit/asyn/transaction/test_owner_reserve_fee.py
• xrpl/asyncio/transaction/main.py

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[xrplf-ai-reviewer]

Small, well-scoped fix removing VAULT_CREATE from the owner-reserve fee branch so VaultCreate autofills with the base fee instead of a 2 XRP reserve, matching rippled 3.2.0+ behavior and the equivalent xrpl.js fix. The code change is minimal and correct; the new unit test file properly verifies AccountDelete/AMMCreate still pay the owner reserve while VaultCreate pays the base fee. No issues found in the actual diff.