Fix task directory gap in upgrade process

The additive extension model refactor moved prompts/contracts/scripts into
.automaton/ but never addressed where tasks live. Two conventions existed:
framework keeps tasks in .automaton/tasks/, Orchestrator creates project
tasks at tasks/.

Fixes:
- Dashboard _find_tasks_dir() now scope-aware: framework mode prefers
  .automaton/tasks/, project mode prefers tasks/ at project root
- migrate-project.sh: if tasks exist in .automaton/tasks/ (old model),
  move them to tasks/ (project root)
- Orchestrator prompt: documents that tasks location depends on scope

scripts/migrate-project.sh

@@ -107,6 +107,18 @@ while IFS= read -r -d '' project_file; do
   fi
 done < <(find "$PROJECT_AUTOMATON" -maxdepth 1 -type f -name "*.md" -o -name "*.sh" -print0 2>/dev/null || true)
 
+# Task directory — old model stored tasks in .automaton/tasks/, new model uses tasks/
+OLD_TASKS="$PROJECT_AUTOMATON/tasks"
+NEW_TASKS="$PROJECT_DIR/tasks"
+if [ -d "$OLD_TASKS" ] && [ ! -e "$NEW_TASKS" ]; then
+  echo "  MOVING   .automaton/tasks/ → tasks/ (tasks should be at project root)"
+  mv "$OLD_TASKS" "$NEW_TASKS"
+  MOVED+=(".automaton/tasks/ -> tasks/")
+elif [ -d "$OLD_TASKS" ] && [ -d "$NEW_TASKS" ]; then
+  echo "  NOTICE   Both .automaton/tasks/ and tasks/ exist — keeping both"
+  KEPT+=(".automaton/tasks/ and tasks/")
+fi
+
 # Report
 echo ""
 echo "=== Migration Summary ==="