Add an end-to-end test for Dijkstra transaction witnessing

Exercise the newly enabled Dijkstra transaction commands end to end:
build-raw, witness and assemble a transaction, asserting the text
envelope types along the way.

Author: palas

.changes/20260828_214439_cardano-cli_palas_dijkstra_witnessing_test.yml

@@ -0,0 +1,6 @@
+description: |
+  Added an end-to-end test covering Dijkstra transaction witnessing: build-raw, witness and assemble, asserting the text envelope types along the way.
+kind:
+- test
+pr: 1432
+project: cardano-cli

cardano-cli/cardano-cli.cabal

@@ -483,6 +483,7 @@ test-suite cardano-cli-golden
     Test.Golden.CreateStaked
     Test.Golden.CreateTestnetData
     Test.Golden.Debug.TransactionView
+    Test.Golden.Dijkstra.Transaction.Assemble
     Test.Golden.ErrorsSpec
     Test.Golden.Genesis.Common
     Test.Golden.Governance.Action

cardano-cli/test/cardano-cli-golden/Test/Golden/Dijkstra/Transaction/Assemble.hs

@@ -0,0 +1,73 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Test.Golden.Dijkstra.Transaction.Assemble where
+
+import Control.Monad (void)
+
+import Test.Cardano.CLI.Util
+
+import Hedgehog (Property)
+import Hedgehog.Extras.Test qualified as H
+
+-- Check that a witness written by `transaction witness` in the Dijkstra era
+-- can be read back by `transaction assemble` to form a transaction.
+-- Regression test for https://github.com/IntersectMBO/cardano-cli/issues/1422
+
+hprop_golden_dijkstra_transaction_assemble_witness_signing_key :: Property
+hprop_golden_dijkstra_transaction_assemble_witness_signing_key =
+  watchdogProp . propertyOnce $ H.moduleWorkspace "tmp" $ \tempDir -> do
+    txBodyFile <- noteTempFile tempDir "tx-body"
+
+    -- Create tx body file
+    void $
+      execCardanoCLI
+        [ "dijkstra"
+        , "transaction"
+        , "build-raw"
+        , "--tx-in"
+        , "2392d2b1200b5139fe555c81261697b29a8ccf561c5c783d46e78a479d977053#0"
+        , "--tx-out"
+        , "addr1q94cxl99qvtwunsqqv6g9mgj3zrawtpt4edsgwxkjtwpy5dsezcht90tmwfur7t5hc9fk8hjd3r5vjwec2h8vmk3xh8s7er7t3+100"
+        , "--fee"
+        , "12"
+        , "--tx-body-file"
+        , txBodyFile
+        ]
+
+    -- Sign it with a single signing key, as a detached witness file
+    witnessFile <- noteTempFile tempDir "single-signing-key-witness"
+    signingKeyFile <-
+      noteInputFile "test/cardano-cli-golden/files/input/conway/keys/payment_keys/signing_key"
+
+    void $
+      execCardanoCLI
+        [ "dijkstra"
+        , "transaction"
+        , "witness"
+        , "--tx-body-file"
+        , txBodyFile
+        , "--signing-key-file"
+        , signingKeyFile
+        , "--mainnet"
+        , "--out-file"
+        , witnessFile
+        ]
+
+    H.assertFileOccurences 1 "TxWitness DijkstraEra" witnessFile
+
+    -- Assemble the body and the witness back into a signed transaction
+    signedTxFile <- noteTempFile tempDir "signed-tx"
+    void $
+      execCardanoCLI
+        [ "dijkstra"
+        , "transaction"
+        , "assemble"
+        , "--tx-body-file"
+        , txBodyFile
+        , "--witness-file"
+        , witnessFile
+        , "--out-file"
+        , signedTxFile
+        ]
+
+    H.assertFileOccurences 1 "Tx DijkstraEra" signedTxFile