Switch create-plan artifacts to ai_plan and enforce gitignore commit

skills/create-plan/opencode/templates/continuation-runbook.md

@@ -28,7 +28,7 @@ Do NOT reference planner-private files during implementation.
 
 ## Mandatory Execution Workflow
 
-Work from this folder (`docs/plans/YYYY-MM-DD-<short-title>/` or repo-specific `docs/plan/...`) and always follow this order:
+Work from this folder (`ai_plan/YYYY-MM-DD-<short-title>/`) and always follow this order:
 
 1. Read `continuation-runbook.md` first.
 2. Execute stories milestone by milestone.
@@ -51,7 +51,7 @@ Work from this folder (`docs/plans/YYYY-MM-DD-<short-title>/` or repo-specific `
 
 ## Git Note
 
-If `docs/plan` or `docs/plans` is gitignored, that is expected and acceptable. Do not treat inability to commit plan-file updates as an error. These files are local planning artifacts.
+`ai_plan/` is intentionally local and must stay gitignored. Do not treat inability to commit plan-file updates inside `ai_plan/` as an error.
 
 ---
 

skills/create-plan/opencode/templates/milestone-plan.md

@@ -93,7 +93,7 @@
 
 ## Related Plan Files
 
-This file is part of the plan folder under `docs/plans/` (or `docs/plan/` if that repo convention is used):
+This file is part of the plan folder under `ai_plan/`:
 - `original-plan.md` - Original approved plan (reference for original intent)
 - `final-transcript.md` - Final planning transcript (reference for rationale/context)
 - `milestone-plan.md` - This file (full specification)