Block-on-commit with inline signature response

[eddyashton]

Implementing #7781.

• Signature cache subsystem: New SignatureCacheSubsystem captures signature, COSE signature, and serialised merkle tree via global commit hooks on the KV tables, making recent signature data available for inline receipt construction.
• Block-until-commit with receipts: New ConsensusCommittedEndpointFunction callback signature passes a CommittedTxInfo struct containing all receipt leaf components (write set digest, commit evidence, claims digest), enabling commit callbacks to build full transaction receipts inline.
• Receipt builder helper: build_receipt_for_committed_tx() reconstructs the merkle tree from cached data, extracts a proof for the specific seqno, and assembles a complete TxReceiptImpl — available for any endpoint to embed receipts in their own response format.
• Write set observer refactor: Changed the write_set_observer callback to pass the digest (not raw bytes), and moved get_commit_evidence() formatting into the encryptor to eliminate duplication across committable_tx.h, historical_queries.h, and the new receipt path.
• E2e tests: Extended test_blocking_calls to cover all three endpoint variants (non-blocking, blocking, blocking-with-receipt) with receipt verification via verify_receipt, and added invalidation testing for the receipt path in partitions_test.py.

[Copilot]

Pull request overview

This PR adds support for returning transaction receipts inline from block-until-commit endpoints by caching recent signature material at commit time and extending the consensus-committed callback to include receipt leaf components.

Changes:

• Introduces a SignatureCacheSubsystem that captures recent signature/COSE signature/serialised Merkle tree data via global commit hooks.
• Updates the consensus-committed endpoint callback API to pass a CommittedTxInfo struct, enabling inline receipt construction on commit.
• Extends sample logging app + OpenAPI schema and e2e tests to cover a new blocking-with-receipt endpoint and invalidation paths.

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/partitions_test.py	Extends invalidation test to cover receipt-capable blocking endpoint.
tests/e2e_logging.py	Adds receipt endpoint to blocking/non-blocking timing tests and verifies returned receipts.
src/node/snapshotter.h	Updates write-set observer to accept a digest directly.
src/node/signature_cache_subsystem.h	New subsystem caching recent signatures/trees for inline receipt construction.
src/node/signature_cache_interface.h	New node subsystem interface for querying cached signature material.
src/node/rpc_context_impl.h	Adds claims digest getter and expands respond-on-commit stored info.
src/node/rpc/frontend.h	Captures write set digest + commit evidence at commit time for later commit callbacks.
src/node/node_state.h	Wires signature cache hook registration into node startup.
src/node/historical_queries.h	Uses encryptor helper to format commit evidence, removing duplication.
src/kv/kv_types.h	Adds AbstractTxEncryptor::get_commit_evidence() helper.
src/kv/committable_tx.h	Refactors commit evidence formatting and changes write-set observer to pass digest.
src/http/http_session.h	Builds CommittedTxInfo and invokes new consensus-committed callback signature.
src/endpoints/endpoint_registry.cpp	Adds receipt builder helper + “respond with receipt on commit” callback factory.
src/enclave/enclave.h	Installs SignatureCacheSubsystem in the node context.
samples/apps/logging/logging.cpp	Adds /log/blocking/private/receipt endpoint using inline receipt response.
include/ccf/rpc_context.h	Adds get_claims_digest() to the public RpcContext interface.
include/ccf/endpoint_registry.h	Exposes new receipt-on-commit helpers in the public endpoint registry API.
include/ccf/endpoint_context.h	Introduces CommittedTxInfo and updates consensus-committed callback type.
doc/schemas/app_openapi.json	Updates sample app OpenAPI version and documents new receipt endpoint path.

[Copilot]

Pull request overview

Copilot reviewed 22 out of 22 changed files in this pull request and generated 4 comments.