forestat v1.2.0

New Features

• Exported FittingEvaluationIndex() for calculating model fitting evaluation indices.
• Added the birch, larch, and picea datasets and their documentation.

Other

• Updated the forestat vignette with usage examples for the new datasets and exported function.
• Cleaned coordinate encodings and missing-coordinate placeholders in the new birch and larch datasets and trimmed picea plot identifiers.
• Corrected field definitions and units in the documentation for the new datasets.
• Added input validation and finite-value handling to FittingEvaluationIndex().
• Previously released datasets and exported functions remain unchanged.
• Improved portability of the PDF manual and model-fitting examples across CRAN check platforms.