feat(mission-control): give the list handler its own review task

"Let Claude handle it" now creates one ClaudeDo task per run to host the
ConPTY session (Idle/IsManual, never queued) instead of an untracked
ad-hoc tile, so the run has a real title, diff, and review outcome.
Since the handler merges its own changes straight into the list's
working dir, the task never gets a WorktreeEntity; its review range
lives as new HandlerBaseCommit/HandlerHeadCommit columns on TaskEntity
instead, reusing the existing commit-range diff machinery and keeping
it out of the worktrees overview entirely.

src/ClaudeDo.Data/Migrations/ClaudeDoDbContextModelSnapshot.cs

@@ -416,6 +416,14 @@ namespace ClaudeDo.Data.Migrations
                         .HasColumnType("TEXT")
                         .HasColumnName("finished_at");
 
+                    b.Property<string>("HandlerBaseCommit")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("handler_base_commit");
+
+                    b.Property<string>("HandlerHeadCommit")
+                        .HasColumnType("TEXT")
+                        .HasColumnName("handler_head_commit");
+
                     b.Property<bool>("IsManual")
                         .ValueGeneratedOnAdd()
                         .HasColumnType("INTEGER")