fix(backlog): disable cross-branch task scanning to prevent ghost tasks

With worktrees, check_active_branches and remote_operations scan other
branches and pull in tasks that were already completed/archived on main
but still exist in backlog/tasks/ on older branches. This bloats the
kanban with ghost tasks (e.g. task-313 through task-327).

Set both to false in backlog/config.yml and document the rationale in
AGENTS.md.

Author: pythoninthegrass

AGENTS.md

@@ -226,6 +226,10 @@ This project uses Backlog.md MCP for all task and project management.
 
 **IMPORTANT**: Use `task_edit(status: "Done")` to mark tasks as done. Do NOT use `task_complete` unless the user explicitly asks to archive/clean up — it removes the task from the kanban.
 
+### Cross-Branch Task Scanning (disabled)
+
+`check_active_branches` and `remote_operations` are both **disabled** in `backlog/config.yml`. With worktrees, these features scan other branches and pull in tasks that were already completed/archived on `main` but still exist in `backlog/tasks/` on older branches — bloating the kanban with ghost tasks. Do not re-enable without accounting for worktree branch divergence.
+
 ### Multiline Field Gotcha
 
 The `finalSummary`, `description`, `implementationNotes`, and `planSet` MCP parameters are single-line JSON strings. Literal `\n` sequences are NOT interpreted as newlines — they render as the two characters `\` `n` in the markdown file. To write multiline content:

backlog/config.yml

@@ -5,9 +5,9 @@ date_format: yyyy-mm-dd
 max_column_width: 80
 auto_open_browser: true
 default_port: 6420
-remote_operations: true
+remote_operations: false
 auto_commit: false
 bypass_git_hooks: false
-check_active_branches: true
+check_active_branches: false
 active_branch_days: 30
 task_prefix: "task"