7.0.0-dev6

Added

• Support for Turin attestations (#7499)
• verify_attestation script to fetch endorsements from AMD and check the provided attestation against them (#7499)
• PreVote optimistaion enabled. This requires that a follower checks that it could be elected before becoming a candidate. This optimisation improves the availablilty of Raft when there are omission faults like partial network partitions. (#7462)
• ProposeRequestVote on SIGTERM. When a primary, with ignore_first_sigterm receives the first SIGTERM, it nominates a successor, allowing the successor to skip waiting for the election timeout and call an election right away. (#7514)

Changed

• Start nodes now confirm that read-only ledger directories are empty on startup (#7355).
• In the C++ API, the method get_txid() on ccf::kv::ReadOnlyStore has been renamed to current_txid(). This may affect historical query code which works directly with the returned StorePtr (#7477).
• The C++ API for installing endpoints with local commit handlers has changed. These handlers should now be added to an Endpoint with .set_locally_committed_function(handler), and the make_[read_only_]endpoint_with_local_commit_handler methods on EndpointRegistry have been removed (#7487).
• The format of CCF's stdout logging has changed. Each line previously tried to align host logs with enclave logs containing a timestamp offset. Since enclave logs no longer exist, this timestamp is never present, so the padding whitespace has been removed (#7491).
• Introduced ccf::historical::verify_self_issued_receipt to verify COSE CCF receipts against current service identity (#7494).