Route signed tx through ledger constructor (#5285) (#5286)
Stacked follow-up for issue #5285, based on [#5287](https://github.com/cardano-foundation/cardano-wallet/pull/5287) / branch `007-ledger-minting`. ## What changed This PR now contains one narrow API-removal source slice: - `Cardano.Wallet.buildAndSignTransaction` uses `Cardano.Wallet.Shelley.Transaction.Ledger.mkTransaction`. - The obsolete `Cardano.Wallet.Shelley.Transaction.mkTransaction` cardano-api wrapper was removed. - The ledger constructor was renamed from `mkTransactionLedger` to `mkTransaction` now that it owns the production signed path. - The #5285 and #5287 spec artifacts were aligned with the real state: mint plumbing is present; script-witness parity remains the blocker for the unsigned body-builder migration and cert-helper deletion. ## Still out of scope - `mkUnsignedTransaction` still uses the cardano-api body builder. - `Transaction/Voting.hs` and `Transaction/Delegation.hs` are not deleted yet, because their remaining caller still needs the full unsigned body-builder migration first. - Script-witness support remains the next blocker. ## Local verification - `rg -n "mkTransactionLedger" . -S` -> no matches - `rg -n "\\bmkTransaction\\b" lib/wallet/src/Cardano/Wallet/Shelley/Transaction.hs -S` -> no matches - `fourmolu --mode check lib/wallet/src/Cardano/Wallet.hs lib/wallet/src/Cardano/Wallet/Shelley/Transaction.hs lib/wallet/src/Cardano/Wallet/Shelley/Transaction/Ledger.hs` -> pass - `hlint lib/wallet/src/Cardano/Wallet.hs lib/wallet/src/Cardano/Wallet/Shelley/Transaction.hs lib/wallet/src/Cardano/Wallet/Shelley/Transaction/Ledger.hs` -> `No hints` - `git diff --check` -> pass - `nix build .#legacyPackages.x86_64-linux.hsPkgs.cardano-wallet.components.library --no-link` -> exit 0 Refs: #5285, #5243, #5237, #5287.