chore: bring cosmos/evm v0.6.2 onto testnet/donut

[0xNilesh]

Brings develop (now on cosmos/evm v0.6.2) onto testnet/donut.

Branch was cut from develop, then testnet/donut merged into it, so this PR lands clean.

Contents

Two commits from develop:

• 81ba8602 chore: bump cosmos/evm pin to v0.6.2
• b6529dd7 merge of chore: bump cosmos/evm pin to v0.6.2 #352

Net effect on donut is the replace pin: 2d248e1881bb (v0.6.0) → f6a1ba7250e2 (v0.6.2).

Verified locally

• merged clean — no conflicts (go.mod/go.sum resolved by the merge direction)
• evm pin on the result is v0.6.2
• all 40 donut upgrade handlers preserved, evmv060.NewUpgrade() included
• go build ./... clean

Full suite left to CI.

Behavioural notes for donut

No state migration. No proto change, no ConsensusVersion bump, no store keys added/removed on either
side of v0.6.0 → v0.6.2.

What actually changes at runtime:

1. SubBalance now panics on underflow instead of wrapping silently. This is the upstream equivalent of
   our F-2026-18201 statedb fix. A panic in a tx fails that tx (no halt), but any flow currently
   underflowing silently would start failing visibly.
2. Module accounts can no longer have their EVM balance written (v0.6.1 security merge 3524ebc6).
   Verified not to affect Push: all module-sender EVM calls pass value=0, and the
   CallExecuteUniversalTx + DeductGasFeesFromReceipt combination in the inbound path is exercised by
   TestInboundCEAGasAndPayload / TestInboundCEAFundsAndPayload with 0 occurrences of
   not allowed to receive funds. DeductAndBurnFees uses the bank keeper, which never enters the EVM
   statedb path at all.
3. Precompile OOG now propagates as vm.ErrOutOfGas — different error on calls that were already
   running out of gas; no repricing, succeeding txs consume identical gas.
4. Extended-denom accounting: no-op here. Donut sets ExtendedDenom == Denom == upc, and the new code
   is guarded by if GetEVMCoinExtendedDenom() != GetEVMCoinDenom().
5. IBC v2 erc20 ack changes: no-op here. Push wires no IBC v2 stack.

Still to do before deployment (not in this PR)

• an evm-v0.6.2 upgrade handler, following the evm-v0.6.0 precedent (empty StoreUpgrades, named plan
  only so cosmovisor has something to switch on)
• localnet upgrade simulation across the height