gRPC: Update to the latest UTxO RPC v1beta spec

.changes/20260819_160000_cardano-rpc_carbolymer_utxorpc_spec_update.yml

@@ -0,0 +1,10 @@
+project: cardano-rpc
+
+pr: 1303
+
+kind:
+  - feature
+  - breaking
+
+description: |
+  Update the vendored UTxO RPC v1beta proto definitions to the latest upstream utxorpc/spec (v0.19.2 plus unreleased EvalReport tweaks), including resetting FetchBlock to the upstream repeated request/response shape (the single-item variant moved to the upcoming utxorpc v1). Expose all v1beta service methods: the unimplemented ones (ReadData, ReadTx, ReadEraSummary, ReadState, ReadMempool, WaitForTx, WatchMempool, DumpHistory) respond with the UNIMPLEMENTED gRPC status. Populate the new `Tx.votes` field (governance votes, Conway onwards) and the new `TxOutput.original_cbor` field (canonical re-encoding of the output; the ledger does not retain the original on-chain TxOut bytes).

cardano-rpc/README.md

@@ -7,17 +7,22 @@ It implements [UTxO RPC](https://utxorpc.org/introduction) protobuf communicatio
 
 ## UTxO RPC v1beta spec coverage
 
+Methods marked ⬜ or ❌ are exposed by the server but respond with the `UNIMPLEMENTED` gRPC status.
+Methods marked ❌ cannot be served by `cardano-node` at all: they need a whole-chain index (transaction by hash, datum by hash) that the node does not maintain, and supporting them would mean building an external chain indexer into the node.
+Use a dedicated chain indexing service for those.
+
 ### [QueryService](https://utxorpc.org/query/spec/)
 
 | Method | Status |
 |--------|--------|
 | [ReadParams](https://utxorpc.org/query/spec/#readparamsrequest) | ✅ Supported |
 | [ReadUtxos](https://utxorpc.org/query/spec/#readutxosrequest) | ✅ Supported |
 | [SearchUtxos](https://utxorpc.org/query/spec/#searchutxosrequest) | ✅ Supported |
-| [ReadData](https://utxorpc.org/query/spec/#readdatarequest) | ⬜ Not supported |
-| [ReadTx](https://utxorpc.org/query/spec/#queryservice) | ⬜ Not supported |
+| [ReadData](https://utxorpc.org/query/spec/#readdatarequest) | ❌ Not supported, needs a chain indexer |
+| [ReadTx](https://utxorpc.org/query/spec/#queryservice) | ❌ Not supported, needs a chain indexer |
 | [ReadGenesis](https://utxorpc.org/query/spec/#queryservice) | ✅ Supported |
 | [ReadEraSummary](https://utxorpc.org/query/spec/#queryservice) | ⬜ Not supported |
+| [ReadState](https://utxorpc.org/query/spec/#queryservice) | ⬜ Not supported |
 
 ### [SubmitService](https://utxorpc.org/submit/spec/)