Skip init if coverage id is available

[matthiasgeihs]

Explanation

Currently the Shield Controller calls the /init endpoint every time a coverage request is made.
This PR implements an optimization where the /init endpoint is skipped if the coverage Id is already available.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed, highlighting breaking changes as necessary
• I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes

---

Note

Coverage checks now accept a request object with optional coverageId to skip /init; controller, backend, types, tests, and changelog updated accordingly.

• Breaking API:
  • Update ShieldBackend to accept request objects: checkCoverage({ txMeta, coverageId? }), checkSignatureCoverage({ signatureRequest, coverageId? }) with new types CheckCoverageRequest and CheckSignatureCoverageRequest.
  • CHANGELOG.md: note breaking change for checkCoverage.
• Backend (src/backend.ts):
  • ShieldRemoteBackend skips v1/*/coverage/init when coverageId is provided; otherwise performs init then polls result.
• Controller (src/ShieldController.ts):
  • Pass latest stored coverageId via #getLatestCoverageId to checkCoverage and checkSignatureCoverage to enable init-skip.
• Tests/Utils:
  • Update expectations to new call shape and add setupCoverageResultReceived helper; adjust simulation flow and mocks (e.g., MOCK_COVERAGE_ID).

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