ICS20-V2 audit follow up issues

[chatton]

Summary

Tracker issue for audit follow up issues

Tracker document: https://www.notion.so/interchain/ICS20-v2-multi-denom-alpha-audit-686033af155343b580165eed1bd30022

• Check how protojson vs std json marshal the new fields.
  • Demonstrated in this PR: test: ics20-v2 packet data encoding compatibility #6218
  • Disallow unknown fields in json encoding: https://github.com/cosmos/ibc-go/pull/6428/files
• Ledger support regression for MsgTransfer with ics20-2 #6465
• Mark token field as deprecated (MsgTransfer) #6471
• Rename ExtractDenomFromFullPath to ExtractDenomFromPath chore: rename ExtractDenomFromFullPath to ExtractDenomFromPath #6464
• Write e2e test for downgrading from v2 to v1 (Carlos: will add it here tests(e2e): ics20 v2 multidenom #6290).
• Add a helper method that gets the AppVersion and returns the unmarshalled packet data. #6472
• Add helper function for packet data construction based on version (chore: move logic for getting packet data to its own function #6475)
• Event type denomation_trace → denom / denomination (chore: rename denomination_trace event type to denomination #6467)
• Emit tokens in events as Json encoded. #6473
• Rename refundPacketToken to refundPacketTokens (chore: rename refundPacketToken to refundPacketTokens #6463)
• Fix compatibility tests: there are failures running main against the tags (e2e: set transfer version depending on the chains' version #6515).
• Look into transfer_authz code and write tests to cover all cases. #6474
  • Index into allocation instead of assigning to var
  • Update the spend limit field instead of re-creating the full type.
  • Instead of Sub ing from the array of coins (SpendLimit), do a Sub on the specific coin for that denom.
  • Consume gas in token iteration of transfer authorization.
• Socialize in cosmos-tech, community call, etc the change of transfer events.

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