cardano-testnet: add RPC ReadEraSummary test

[carbolymer]

Description

Adds a UTxO RPC ReadEraSummary integration test to cardano-testnet.

• The new hprop_rpc_read_era_summary test calls the QueryService.ReadEraSummary method over gRPC and verifies the returned era summaries are a prefix of the canonical era order, that every era but the last has its end boundary set, that consecutive boundaries line up, and that the first era starts at slot 0, epoch 0.
• Wires the new ReadEraSummary span trace into the node's RPC tracer: forMachine, metrics counter, namespace, severity, documentation and allNamespaces entries.

Stacked on #6657 (and through it on #6668), merge those first.

Note: the server-side ReadEraSummary support (including the TraceRpcQueryReadEraSummarySpan constructor this PR uses) is not part of the released cardano-rpc 11.3.0.0.
It lives on the cardano-api branch mgalazyn/feature/rpc-readerasummary, so CI stays red until that work is released to CHaP and the bound is bumped here.

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. These may include:
  • golden tests
  • property tests
  • roundtrip tests
  • integration tests
    See Running tests for more details
• Any changes are noted in the CHANGELOG.md for affected package
  • cardano-node-chairman, cardano-submit-api and cardano-testnet instead need a
    changelog fragment in <package>/.changes/, because their CHANGELOG.md is generated
    from fragments at release time. Copy _TEMPLATE.yml from that directory, or run
    nix run github:input-output-hk/cardano-dev#herald -- new
• The version bounds in .cabal files are updated
• CI passes. See note on CI. The following CI checks are required:
  • Code is linted with hlint. See .github/workflows/check-hlint.yml to get the hlint version
  • Code is formatted with stylish-haskell. See .github/workflows/stylish-haskell.yml to get the stylish-haskell version
  • Code builds on Linux, MacOS and Windows for ghc-9.6 and ghc-9.12
• Self-reviewed the diff

Note on CI

If your PR is from a fork, the necessary CI jobs won't trigger automatically for security reasons.
You will need to get someone with write privileges. Please contact IOG node developers to do this
for you.