Vue 3 best practices, common gotchas, and performance optimization. Reactivity - Accessing ref() values without .value in scripts → See ref-value-access - Destructuring reactive() objects, losing reactivity → See reactive-destructuring - Choosing between ref() and reactive() for state → See prefer-ref-over-reactive - Accessing refs inside arrays and collections → See refs-in-collections-need-value - Large objects or external library data overhead → See shallow-ref-for-performance - Using nested refs in template expressions → See template-ref-unwrapping-top-level - Comparing reactive objects w…