- Canonicalize anchors in dedupe keys to handle whitespace variants
- Make lines field required in edit operations
- Only allow unanchored append/prepend to create missing files
- Reorder delete/rename validation to prevent edge cases
- Add allow_non_gpt_model and max_prompt_tokens to config schema
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Unify internal hashline edit handling around replace/append/prepend to remove legacy operation shapes. This keeps normalization, ordering, deduplication, execution, and tests aligned with the new op/pos/end/lines contract.