Bound spatial OCR pair generation before materialization

Spatial OCR association must bound label-value matching before constructing candidate objects. A naïve all-labels-by-all-values loop becomes quadratic on dense or adversarial OCR and can consume large memory while blocking a synchronous request path. Cap eligible geometry tokens, restrict candidates with coarse row or distance buckets, and retain only the nearest few values per label before detailed scoring. The bound should fail closed or fall back safely when exceeded. Character limits alone are not a sufficient computational limit because short labels and numbers still produce many tokens.

Applies when: synchronous OCR parsing scores spatial relationships between many labels and values. Keywords: OCR, geometry, quadratic complexity, candidate pairs, denial of service, performance, bounds