[datlechin]

Summary

• A connect that fails with no named cause now probes each host this Mac dials (the database host or host list, the first SSH hop, the SOCKS proxy) with a UDP NWConnection. When macOS 15 Local Network privacy refuses every one, the pane reads Local Network Access Required, names the host, and offers Open System Settings beside Try Again.
• The driver's text moves to Copy Details (ConnectionFailureInfo.details); the pane headline comes from ConnectionFailureInfo.title.
• Test Connection, the Welcome window and launch intents get the same error and button through ConnectionFailureClassifier.recoveryAction.
• Not probed: errors raised before any socket opens (ConnectionPreflightReporting on SOCKS, SSH and tunnel errors), errors a sign-in provider claims, and a host list with one reachable server.
• UnavailableStateView caps only its text at 420 points. The button row shared that cap and truncated its titles ("Manage Connec…" with three buttons, "Open Syst…" with four).
• SSH first-hop errors keep strerror: an immediate connect failure dropped it, and the poll path read errno after close().
• macOS 27 ignores the Privacy_LocalNetwork anchor and opens Privacy & Security (measured against Privacy_AllFiles, which lands on Full Disk Access), so the recovery text names the last step.

Test plan

• LocalNetworkAccessProbeTests: verdicts from injected path and state results (refused path, satisfied path reporting .notAvailable, mDNS PolicyDenied, NoSuchRecord, ready, ended); a real loopback probe is granted.
• LocalNetworkAccessDiagnosisTests: hops per transport, SSH alias and jump host resolution, loopback never named, mixed host list, preflight and sign-in errors.
• LocalNetworkConnectFailureTests: ensureConnected through the fake SQL Server driver records .connectFailed(info, .openLocalNetworkSettings) on a refusal, keeps the driver error when granted, keeps SOCKSProxyError.invalidConfiguration, and records nothing when cancelled mid-probe.
• ConnectionFailureClassifierTests, ConnectionRecoveryPresentationTests, UnavailableStateViewLayoutTests (a 560-point action row keeps its width; the old cap held it to 420).
• A real refusal was not produced: denying the permission here would change TCC for the installed TablePro. The refusal path rests on TN3179 and the iOS probe from iOS: LocalNetworkPermission classifies by address range and infers permission state #2040.

Screenshots

The pane rendered from ConnectionUnavailableView with a database host refused. Before is the text main shows for the same failure; on main its buttons were also truncated.

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Before
After

Docs: TableProApp/docs#62

Fixes #3668