Add HOLLAR routes between Hydration and AssetHub

[hitchho]

What

Adds XCM support for HOLLAR (Hydration asset 222 / AssetHub foreign asset {Parachain(2034), GeneralIndex(222)}) between Hydration and AssetHub, both directions.

• hollar asset + registration on both chains (18 decimals, 0.02 ED/minBalance, verified on-chain)
• Hydration side reads balances from the GHO erc20 (0x531a654d1696ED52e7275A8cede955E82620f99a) via balanceId + evm().erc20()
• assethub → hydration: DestinationReserve (burns the hub derivative, withdraws from AssetHub's sovereign on Hydration), dest fee 0.02 HOLLAR
• hydration → assethub: LocalReserve for the asset with the destination fee paid in DOT via DestinationReserve — HOLLAR has no fee-payment pool on AssetHub (BuyExecution in HOLLAR fails TooExpensive, verified via DryRunApi.dry_run_xcm). This required a small builder extension: optional feesTransferType on polkadotXcm().transferAssetsUsingTypeAndThen() (maps to the pallet's native fees_transfer_type arg)

Bug fixes surfaced along the way

• transferAssetsUsingTypeAndThen emitted unsorted Assets vectors. The runtime only decodes Assets sorted by canonical Location order, and the builder unconditionally placed the fee first. Any fee/asset pair ordered the wrong way (e.g. DOT parents:1 fee with a parents:0 local asset) produced an extrinsic the runtime rejects with an opaque wasm trap (Bad input data) in both DryRunApi and validate_transaction. Added a canonical location comparator (parents → interior arity → junction variant/value, mirroring the runtime's derived Ord) and order the pair accordingly. This was originally misdiagnosed as a runtime issue — see Not a bug: unsorted XCM v4 Assets vector fails SCALE decode, surfaces as opaque wasm trap (client-side, fixed in sdk#343) hydration-node#1491 (closed with the analysis)
• HydrationEvmResolver.toH160 was wrong for native substrate accounts: it unconditionally unwrapped bytes 4..-8, which is only correct for ETH\0-prefixed EVM accounts; native accounts must truncate to the first 20 bytes (mirrors pallet-evm-accounts::evm_address). Needed for erc20 balance reads of substrate-held HOLLAR

Verification (mainnet dry runs)

• assethub → hydration: dry_run_call on AssetHub succeeds (ForeignAssets burn) and the forwarded XCM executes Complete on Hydration via dry_run_xcm. AssetHub's sovereign on Hydration backs the hub supply 1:1 (~417k HOLLAR)
• hydration → assethub: dry_run_call on Hydration succeeds (DOT fee + erc20 HOLLAR withdrawn to AH sovereign, WithdrawAsset(DOT) → BuyExecution(DOT) → ReserveAssetDeposited(HOLLAR) → DepositAsset forwarded) and the forwarded XCM executes Complete on AssetHub via dry_run_xcm
• xc-cfg builds and unit tests pass; verified end-to-end in hydration-ui against mainnet

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🦋 Changeset detected

Latest commit: e255fa9

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@galacticcouncil/xc-cfg	Minor

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