Dragging a session tab to split in the Bot workspace committed through
openSessionTile with no scope, whose default { workspaceMode: 'sessions' }
was written onto the already-open tile before the pane move — so the tile
re-bucketed into the Sessions workspace and vanished from the Bot strip.
A scope-less open of an already-open tile is a MOVE, not a re-scope:
default the scope to the tile's current workspaceMode and only rewrite
scope when the caller passed one explicitly (sidebar/bot openers still
win). Brand-new tiles keep the 'sessions' default.
Closes#96865
Supersedes #96998
Co-authored-by: Teknium <127238744+teknium1@users.noreply.github.com>
liguoyu
1592e48ac9