27-gmp: exported genesis fails validation/import once an ICS27 account has a non-local (EVM / foreign-prefix) sender #9072

Summary of Bug

types.GenesisState.Validate and keeper.InitGenesis in modules/apps/27-gmp validate RegisteredICS27Account.AccountId.Sender with sdk.AccAddressFromBech32:

// modules/apps/27-gmp/types/genesis.go
if _, err := sdk.AccAddressFromBech32(account.AccountId.Sender); err != nil {
    return errorsmod.Wrapf(ibcerrors.ErrInvalidAddress, "string could not be parsed as address: %v", err)
}

The sender of a GMP packet is an identifier on the counterparty chain — an EVM hex address (0x1234…) or a bech32 address with a foreign prefix (osmo1…). GMPPacketData.ValidateBasic and OnRecvPacket accept it as an opaque string (non-empty, <= MaximumSenderLength), so the account is created and stored. ExportGenesis then produces state that fails its own Validate and cannot be passed to InitGenesis.

Expected Behaviour

An exported genesis should round-trip: ExportGenesis → Validate → InitGenesis. The sender should be validated the same way it is validated on the packet path (presence and length), not as a local bech32 address.

Impact

As soon as one ICS27 account has been created by a remote sender, <appd> export followed by validate-genesis / a restart from the exported genesis fails with decoding bech32 failed: … invalid address.

Version

main (8a8d8134), v11.x.

Steps to Reproduce

k := chain.GetSimApp().GMPKeeper
data := types.NewGMPPacketData("0x1234567890abcdef1234567890abcdef12345678", "", []byte("salt"), []byte{}, "")
_, _ = k.OnRecvPacket(ctx, &data, "07-tendermint-0") // account is created before the (empty) payload fails

gs, _ := k.ExportGenesis(ctx)
err := gs.Validate()
// err: string could not be parsed as address: decoding bech32 failed: invalid checksum ...: invalid address

I have a small patch with an AccountIdentifier.Validate helper (client ID + non-empty/bounded sender + salt length, shared by Validate and InitGenesis) and an export → validate → import regression test; happy to open the PR.