CheckAsync built its own HttpClient inline, so nothing beyond tag
parsing was testable without hitting the real GitHub API. Added an
internal CheckAsync(currentVersion, HttpMessageHandler, ct) overload
(the public method now delegates to it) as a seam for a stub handler,
and tests for the full best-effort matrix: newer/equal/older/unparseable
tag, missing html_url, HTTP error status, malformed JSON, a thrown
HttpRequestException, and an unparseable local version — all of which
must resolve to null or the correct LatestRelease, never throw.
Real loopback TCP socket speaking newline-delimited JSON-RPC 2.0, optionally
TLS with a self-signed certificate, with per-method handlers and call
counters. Lets ElectrumClient, WalletSynchronizer, TransactionInspector, and
CertificatePinStore be exercised against the same code paths used in
production instead of being mocked.
Also exposes UpdateChecker's tag-parsing logic internally so its version
comparison can be tested without a real GitHub API call.
Compares the running assembly version against the latest GitHub release
tag on every app launch (desktop and Android) and shows an in-app
overlay with the new version tag when one is available. Best-effort:
network/parse failures are silent, matching the app's existing
non-blocking startup checks.
davide