Reorganize internal codecs (master) (ACINQ#1732)

The goal is to ensure maximum safety when migrating data.

To achieve this, we strictly segregate each codec version (to make sure
that we don't accidentally mix codec versions), while still letting
tests access each unitary codecs (which using inner `private classes`
would have prevented). Relevant tests only need to be moved to the
appropriate package.

The package structure is now:

```
wire
 |
 `-- internal
 |       |
 |       `-- channel
 |       |      |
 |       |      `-- version0
 |       |      |      |
 |       |      |      `-- ChannelCodecs0
 |       |      |
 |       |      `-- version1
 |       |      |      |
 |       |      |      `-- ChannelCodecs1
 |       |      |
 |       |      `-- ChannelCodecs
 |       |
 |       `-- CommandCodecs
 |
 `-- others
```

Co-authored-by: Bastien Teinturier <31281497+t-bast@users.noreply.github.com>

eclair-core/src/main/scala/fr/acinq/eclair/blockchain/electrum/db/sqlite/SqliteWalletDb.scala

@@ -16,15 +16,14 @@
 
 package fr.acinq.eclair.blockchain.electrum.db.sqlite
 
-import java.sql.Connection
-
 import fr.acinq.bitcoin.{BlockHeader, ByteVector32, Transaction}
 import fr.acinq.eclair.blockchain.electrum.ElectrumClient.{GetMerkleResponse, TransactionHistoryItem}
 import fr.acinq.eclair.blockchain.electrum.ElectrumWallet.PersistentData
 import fr.acinq.eclair.blockchain.electrum.db.WalletDb
 import fr.acinq.eclair.blockchain.electrum.{ElectrumClient, ElectrumWallet}
 import fr.acinq.eclair.db.sqlite.SqliteUtils
 
+import java.sql.Connection
 import scala.collection.immutable.Queue
 
 class SqliteWalletDb(sqlite: Connection) extends WalletDb {
@@ -135,7 +134,6 @@ class SqliteWalletDb(sqlite: Connection) extends WalletDb {
 
 object SqliteWalletDb {
 
-  import fr.acinq.eclair.wire.ChannelCodecs._
   import fr.acinq.eclair.wire.CommonCodecs._
   import scodec.Codec
   import scodec.bits.BitVector
@@ -152,8 +150,6 @@ object SqliteWalletDb {
 
   def deserializeMerkleProof(bin: Array[Byte]): GetMerkleResponse = proofCodec.decode(BitVector(bin)).require.value
 
-  import fr.acinq.eclair.wire.LightningMessageCodecs._
-
   val statusListCodec: Codec[List[(ByteVector32, String)]] = listOfN(uint16, bytes32 ~ cstring)
 
   val statusCodec: Codec[Map[ByteVector32, String]] = Codec[Map[ByteVector32, String]](
@@ -168,6 +164,8 @@ object SqliteWalletDb {
     (wire: BitVector) => heightsListCodec.decode(wire).map(_.map(_.toMap))
   )
 
+  val txCodec: Codec[Transaction] = lengthDelimited(bytes.xmap(d => Transaction.read(d.toArray), d => Transaction.write(d)))
+
   val transactionListCodec: Codec[List[(ByteVector32, Transaction)]] = listOfN(uint16, bytes32 ~ txCodec)
 
   val transactionsCodec: Codec[Map[ByteVector32, Transaction]] = Codec[Map[ByteVector32, Transaction]](

eclair-core/src/main/scala/fr/acinq/eclair/db/pg/PgChannelsDb.scala

@@ -23,7 +23,7 @@ import fr.acinq.eclair.db.ChannelsDb
 import fr.acinq.eclair.db.DbEventHandler.ChannelEvent
 import fr.acinq.eclair.db.Monitoring.Metrics.withMetrics
 import fr.acinq.eclair.db.pg.PgUtils.DatabaseLock
-import fr.acinq.eclair.wire.ChannelCodecs.stateDataCodec
+import fr.acinq.eclair.wire.internal.channel.ChannelCodecs.stateDataCodec
 import grizzled.slf4j.Logging
 
 import java.sql.Statement

eclair-core/src/main/scala/fr/acinq/eclair/db/pg/PgPendingRelayDb.scala

@@ -22,7 +22,7 @@ import fr.acinq.eclair.channel.{Command, HtlcSettlementCommand}
 import fr.acinq.eclair.db.Monitoring.Metrics.withMetrics
 import fr.acinq.eclair.db.PendingRelayDb
 import fr.acinq.eclair.db.pg.PgUtils._
-import fr.acinq.eclair.wire.CommandCodecs.cmdCodec
+import fr.acinq.eclair.wire.internal.CommandCodecs.cmdCodec
 import javax.sql.DataSource
 
 import scala.collection.immutable.Queue

eclair-core/src/main/scala/fr/acinq/eclair/db/sqlite/SqliteChannelsDb.scala

@@ -23,7 +23,7 @@ import fr.acinq.eclair.db.ChannelsDb
 import fr.acinq.eclair.db.DbEventHandler.ChannelEvent
 import fr.acinq.eclair.db.Monitoring.Metrics.withMetrics
 import fr.acinq.eclair.payment.{ChannelPaymentRelayed, PaymentEvent, PaymentReceived, PaymentRelayed, PaymentSent}
-import fr.acinq.eclair.wire.ChannelCodecs.stateDataCodec
+import fr.acinq.eclair.wire.internal.channel.ChannelCodecs.stateDataCodec
 import grizzled.slf4j.Logging
 
 import java.sql.{Connection, Statement}

eclair-core/src/main/scala/fr/acinq/eclair/db/sqlite/SqlitePendingRelayDb.scala

@@ -22,7 +22,7 @@ import fr.acinq.bitcoin.ByteVector32
 import fr.acinq.eclair.channel.{Command, HtlcSettlementCommand}
 import fr.acinq.eclair.db.Monitoring.Metrics.withMetrics
 import fr.acinq.eclair.db.PendingRelayDb
-import fr.acinq.eclair.wire.CommandCodecs.cmdCodec
+import fr.acinq.eclair.wire.internal.CommandCodecs.cmdCodec
 
 import scala.collection.immutable.Queue