aquats 1.2.0

aquats v1.2.0 - Initial Public Release

• Regression Suite: Linear, allometric power ($y = a \cdot x^b$), exponential, polynomial, and cubic models.
• Community Ecology: NMDS, PCA, RDA, distance-based RDA, and Mantel test networks.
• Diversity & Accumulation: Alpha diversity indices (Shannon, Simpson, Chao1, Pielou) and species accumulation curves.
• Environmental Assessment: WAWQI index and heavy metal contamination metrics (CF, CD, PLI, HPI, HEI).
• Metadata & Vignettes: Fully documented with a reproducible vignette and formal citation support.