Add --suite thumb while retaining default ARM preparation. Verify hashes, the Thumb-to-ARM evaluation bridge, and the result checkpoint; retain upstream provenance outside tracked files. Expand offline synthetic adapter and CLI regressions.
Darwin arm64 baseline: the unmodified Thumb ROM reaches ARM eval at 0x08000934 after 771 steps with r7=229 in debug and release. ARM remains passing. Online/offline preparation agrees and all 21 Python tests pass. CPU behavior is unchanged.
