review_task/continue_merge on a planning parent always leaves conflicts in
the tree, and the UI auto-opened the resolver on every PlanningMergeConflict
broadcast regardless of who started the merge -- so a running Claude session
resolving a unit-merge conflict could race a human editing the same shared
checkout in a resolver window neither of them asked for.
PlanningMergeOrchestrator.StartAsync now takes an externallyDriven flag (set
by ExternalMcpService's MCP-driven review_task path, left false for the UI's
ApproveReview) that rides along on the PlanningMergeConflict broadcast. The
UI only auto-opens the resolver when it's false; otherwise it shows a
persistent banner with a manual "Open resolver" button, cleared on
PlanningMergeAborted/PlanningCompleted. A new GetActiveExternalConflictsAsync
query (checked against GitService.IsMidMergeAsync rather than the in-memory
flag alone) lets the UI resync the banner on reconnect instead of trusting a
one-shot broadcast that isn't replayed after a restart.
The childless single-task conflict path was checked and needed no change --
it only broadcasts the generic TaskUpdated, never PlanningMergeConflict.
preview_merge/preview_merge_set now report isEmpty (ahead==0, or
HandlerBaseCommit==HandlerHeadCommit for a worktree-less list-handler
task) instead of leaving an empty branch indistinguishable from a small
one. preview_merge also stops throwing for worktree-less handler tasks,
falling back to their fixed commit range. review_task's parent approve
returns emptyChildren, naming the Done children whose review range
contributed nothing before the unit merge lands. TaskRefDto/TaskDto now
expose roadblockCount so a CLAUDEDO_BLOCKED child is identifiable over
MCP, since it still reaches Done per the unified parent model.
review-merge: worktree-less approvals run the gate too, and all three UI merge
entry points handle verify_failed explicitly.
Ui gotchas: NumericUpDown.Value is decimal? and nulls while the box is empty.