Add explicit force replacement workflow

docs/internal/config.md

@@ -33,6 +33,8 @@ Defaults are applied in `ApplyDefaults`:
 
 Validation requires at least one pipeline, slug-like unique pipeline ids, one source per pipeline, at least one destination, slug-like unique destination ids within each pipeline, backend-specific required fields, valid validation policy, valid publish and transform combinations, and valid transfer actions.
 
+Transfer validation accepts `replace` for `on_destination_newer` and `on_conflict`, but publish planning honors those destructive actions only when the current run explicitly requests force.
+
 `ValidatePublishTransformPolicy` is shared with publish planning so destination policy combinations are checked consistently. Publishing HTML requires an enabled Markdown-to-HTML transform in `sidecar` mode. A publish policy must select source output, HTML output, or both.
 
 ## Executable support boundary