* fix(#2400): warn on planned-phase no-op + sync progress.total_plans
Bug A: When STATE.md Current Position has no recognized labels (narrative
prose), emit a warning field so the workflow detects the no-op instead
of continuing with stale state.
Bug B: Sync progress.total_plans in the YAML frontmatter when a plan
count is provided, preventing contradictory state between frontmatter
(0) and body (actual count). This writes the explicitly-provided count,
not a re-derivation from disk (#500 safe).
Closes#2400
* docs(#2400): backfill changeset PR number (2552)
