Add rebus internal splits for perfect round-trip conversion

[samanpwbb]

Addresses pipe positioning bug where splits within rebus squares were incorrectly positioned during xd → JSON → xd conversion. Previously, JUS[T|A|SK]OSH would convert to JUS[TASK]|O|SH instead of the correct JUST|A|SKOSH.

• BREAKING: changed the interface of resolveFullClueAnswer which is an exposed part of the API, to no longer take rebusMap.
• Added new rebusInternalSplits field to json representation of xd in order to handle splits inside of rebuses
• Improved tests & typing of test files

This will need a major version bump.

[Copilot]

Pull Request Overview

This PR fixes a pipe positioning bug in rebus squares during xd → JSON → xd round-trip conversion by implementing proper tracking and reconstruction of splits within rebus squares.

• Extended the Clue interface to support tracking internal rebus splits
• Completely rewrote the split parsing logic to distinguish between tile boundary and internal rebus splits
• Refactored resolveFullClueAnswer to handle internal rebus splits during answer reconstruction

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
packages/xd-crossword-tools-parser/src/types.ts	Added rebusInternalSplits field to Clue interface for tracking splits within rebus squares
packages/xd-crossword-tools-parser/src/parser/xdparser2.ts	Rewrote parseSplitsFromAnswer to distinguish tile boundary vs internal rebus splits and updated clue creation
packages/xd-crossword-tools/src/JSONtoXD.ts	Completely refactored resolveFullClueAnswer to process tiles individually and handle internal rebus splits
packages/xd-crossword-tools/tests/JSONtoXD.test.ts	Added comprehensive test cases for rebus internal splits and perfect round-trip conversion

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[orta]

Yeah, this is the same the direction my attempt went too, adding additional metadata ahead of time and then re-using that

[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated no new comments.

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[orta]

Breaking changes are fine, we just want a major bump and a note in the changelog for implementors (e.g. TNY)