Add `--blame-crash` support to `DotNetTestSettings`

[BrewingCoder]

Tamp.NetCli.V10.DotNetTestSettings exposes BlameHang and BlameHangTimeout,
which map to --blame-hang / --blame-hang-timeout. There is no corresponding
property for --blame-crash.

These cover different failures. --blame-hang catches a single test exceeding a
time budget. --blame-crash is what you need when the test host process dies:
it writes a sequence file naming the test that was executing at the time, plus a
crash dump.

This mattered concretely. We had a bug where an unhandled exception on a
background thread killed the test host at a different test count on every run
(249, 541, 635). The run reported Test Run Aborted with a bare stack and no
indication of which test was in flight, and the TRX written was truthful but
partial, so it read as a clean pass of a subset. --blame-crash is the
diagnostic that answers "which test was running when the host died", and it was
not reachable through the typed API.

Suggested fix: add BlameCrash (bool) and ideally BlameCrashDumpType
(mini / full), matching the existing BlameHang shape.