Need to handle denom prefixes of <ibc-port>/<ibc-channel>/

[michaelfig]

Describe the bug

To Reproduce

From @simpletrontdip on Discord (https://discord.com/channels/585576150827532298/766087740336635924/943026098986422314):

Pegasus seems to send an IBC package with non-prefixed denom (uphoton instead of pegasus/channel-0/uphoton)

{"amount":"1000000","denom":"uphoton","receiver":"cosmos1h68l7uqw255w4m2v82rqwsl6p2qmkrg08u5mye","sender":"pegasus"}

This makes the target chain treat it as a remote one (although it was sent back)

gaiad q bank balances cosmos1h68l7uqw255w4m2v82rqwsl6p2qmkrg08u5mye --node https://rpc.testnet.cosmos.network:443 --chain-id cosmoshub-testnet
balances:
- amount: "1000000"
  denom: ibc/91CC51904C9E34CD841008CDA73F92811A235501A556EAC7F81B32FAA7F706A7
- amount: "334995400"
  denom: uphoton
pagination:
  next_key: null
  total: "0"

gaiad query ibc-transfer denom-trace 91CC51904C9E34CD841008CDA73F92811A235501A556EAC7F81B32FAA7F706A7 --node https://rpc.testnet.cosmos.network:443

denom_trace:
  base_denom: uphoton
  path: transfer/channel-134

Expected behavior

Pegasus implements denom prefixing semantics for IBC connections, as described in the ICS 20 spec

Notably, when IBC-Pegasus sends remotePegged tokens back to their source, the sent denom string must be prefixed with their source's port and channel, such as: {ics20Port}/{ics20Channel}/{denom}. When IBC-Pegasus receives a packet, localPegged tokens must only be matched if they use the channel's local prefix.

token source	packet sender	action
local	us	no prefix
local	them	verify and strip their prefix
remote	us	add our prefix
remote	them	no prefix

Platform Environment

• what OS are you using? what version of Node.js?
• is there anything special/unusual about your platform?
• what version of the Agoric-SDK are you using? (run git describe --tags --always)

Additional context

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