WorkerHub and IWorkerClient each carried their own copy of every record and
had already drifted — MergePreviewDto lost its verify fields on the client
side, two records disagreed on their name. They now live in Data/Wire.cs and
reach both sides via a <Using> item, so a hub signature change is a compile
error instead of a silently dropped JSON field.
RepoScanner.Scan now recurses into subdirectories (max depth 5) instead
of only checking the immediate children of the chosen folder. A found
repo (.git as dir or file) is added without descending further; the
selected folder itself is checked too. Skips node_modules/bin/obj/.git/
.vs/packages and reparse points (junctions/symlinks). Per-directory
IOException/UnauthorizedAccessException no longer aborts the whole scan.