refactor: remove processed key and handling code (#216)

* refactor: remove processed key and handling code

* refactor: ensure the underlying apps `OnRecvPacket` callback is invoked

* docs: fix broken link to Defund-Labs interquery.

I cannot find a link to the code so this now links to the spec

(cherry picked from commit 8cb681e)

README.md

@@ -78,7 +78,7 @@ Modules and middleware developed by other awesome teams in the ecosystem:
 | Name | Type | Stakeholders | Description |
 | ---- | ---- | ------------ | ----------- |  
 | [Interchain KV Queries](https://github.com/ingenuity-build/interchain-queries) | Module | [Ingenuity](https://github.com/ingenuity-build) | An application that enables on chain querying of another IBC enabled chains state without the need for the chain being queried to implement the application. |
-| [query](https://github.com/defund-labs/defund/tree/main/x/query) | Module | [Defund Labs](https://github.com/defund-labs) | An application that enables on chain querying of another IBC enabled chains state without the need for the chain being queried to implement the application. Similar to the interchain-queries application in the row above but without callbacks. |
+| [query](https://github.com/defund-labs/interquery) | Module | [Defund Labs](https://github.com/defund-labs) | An application that enables on chain querying of another IBC enabled chains state without the need for the chain being queried to implement the application. Similar to the interchain-queries application in the row above but without callbacks. |
 | [NFT Transfer (ICS 721)](https://github.com/bianjieai/nft-transfer) | Module | [Bianjieai](https://github.com/bianjieai) | An application that enables cross chain NFT transfer. |
 | [recovery](https://github.com/evmos/evmos/tree/main/x/recovery) | Middleware | [Evmos](https://github.com/evmos) | Middleware enabling the recovery of tokens sent to unsupported addresses. |
 | [ibc-rate-limit](https://github.com/osmosis-labs/osmosis/tree/main/x/ibc-rate-limit) | Middleware | [Osmosis Labs](https://github.com/osmosis-labs) | Middleware that limits the in or out flow of an asset in a certain time period to minimise the risks of cross chain token transfers. This is implemented as a middleware wrapping ICS20 with the rate limiting logic implemented by cosmwasm contracts. |

middleware/packet-forward-middleware/packetforward/ibc_middleware.go

@@ -198,7 +198,6 @@ func (im IBCMiddleware) OnRecvPacket(
 	metadata := m.Forward
 
 	goCtx := ctx.Context()
-	processed := getBoolFromAny(goCtx.Value(types.ProcessedKey{}))
 	nonrefundable := getBoolFromAny(goCtx.Value(types.NonrefundableKey{}))
 	disableDenomComposition := getBoolFromAny(goCtx.Value(types.DisableDenomCompositionKey{}))
 
@@ -214,14 +213,9 @@ func (im IBCMiddleware) OnRecvPacket(
 		return newErrorAcknowledgement(fmt.Errorf("failed to construct override receiver: %w", err))
 	}
 
-	// if this packet has been handled by another middleware in the stack there may be no need to call into the
-	// underlying app, otherwise the transfer module's OnRecvPacket callback could be invoked more than once
-	// which would mint/burn vouchers more than once
-	if !processed {
-		if err := im.receiveFunds(ctx, packet, data, overrideReceiver, relayer); err != nil {
-			logger.Error("packetForwardMiddleware OnRecvPacket error receiving packet", "error", err)
-			return newErrorAcknowledgement(fmt.Errorf("error receiving packet: %w", err))
-		}
+	if err := im.receiveFunds(ctx, packet, data, overrideReceiver, relayer); err != nil {
+		logger.Error("packetForwardMiddleware OnRecvPacket error receiving packet", "error", err)
+		return newErrorAcknowledgement(fmt.Errorf("error receiving packet: %w", err))
 	}
 
 	// if this packet's token denom is already the base denom for some native token on this chain,

middleware/packet-forward-middleware/packetforward/types/keys.go

@@ -16,7 +16,6 @@ const (
 type (
 	NonrefundableKey           struct{}
 	DisableDenomCompositionKey struct{}
-	ProcessedKey               struct{}
 )
 
 func RefundPacketKey(channelID, portID string, sequence uint64) []byte {