Comparison common records and moved intervals

Source pin: 7338078f8ddd924b8cddee35f512f2286072136d, DiffData.cpp::DoTwoWayDiff, CompareWithIgnoreWS and StickAndSkip.

The engine plan now captures its comparison options alongside the original input lines and filtered keys. Two-pane common-record presentation uses that captured whitespace mode, rather than current preferences, to decide whether a Normal row is hidden by comparison. Equal payloads are hidden even when their EOL differs. Regex/case/comment differences retain FilteredDiff and remain shown in two panes. The source's provisional Whitespace assignment is reset to Normal before its filter classification; the port retains that behavior instead of adding a new visible whitespace state here. Combined neutral aliases retain their separate source conditions and visibility.

An unsplit common record in combined view now uses Mine's text and Base's exact ending, following the source AddData call. This includes all nine recognized styles. Split RemovedWhitespace/AddedWhitespace records retain each side's own ending. Two-pane input records, original encodings and the unedited Mine draft stay independent. Explicit combined export serializes its captured records using Mine's selected encoding. Editing adopts those records through the existing in-place history/save path; merely viewing or exporting does not write inputs.

With moved blocks enabled, adjacent contiguous modified intervals are joined before pairing, following StickAndSkip. The restored whole interval determines row pairing, gap placement and the navigable changed block; move detection still uses the original plan. Disabling moves retains separate intervals. Malformed ranges/common lengths and cancelled presentation work refuse publication.

Grouped evidence records 70 passing focused Core checks, including all 81 recognized ending pairs and the retained pinned moved-block corpus. One Debug build passed with one exit-zero/no-output compiler diagnostic. Four actual native workflows passed on the first grouped attempt: common records, retained whitespace, EOF and moved blocks. One cached receiver compilation links the built app; all four owned processes were reaped and independently absent. Help remained byte-identical to the built bundle; the website renders 261 documents with no unresolved fragments. No new screenshots were needed for these record/serialization changes.

This does not certify complete DiffData/source engine equivalence, every physical gesture, large-file behavior, minimum macOS, VoiceOver or signed Finder/App Store acceptance.