Add selectAll(), dedupe inherited properties, checks for property sha…

[flyon]

…pe overrides, readme updated

feat(core): implement selectAll() with inherited dedupe, stricter overrides, and docs/test updates

• add Shape.selectAll() and nested selectAll() on QueryShape/QueryShapeSet
• add NodeShape.getUniquePropertyShapes() and use it to dedupe inherited property labels (subclass overrides win once)
• tighten selectAll typing by excluding base Shape keys and align top-level/nested inference
• enforce registration-time override tightening for minCount/maxCount/nodeKind
• preserve explicit minCount/maxCount=0 in createPropertyShape
• expand runtime/metadata/type tests for selectAll, override constraints, and zero-count regression
• update README with better examples and overall flow, and CRUD return semantics

[github-actions]

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