feat: v2 built-in functions — 90+ native functions
Array: len, push, pop, filter, map, concat, contains, reverse, slice,
indexOf, find, some, every, flat, sort (mutating ops re-trigger signal)
Math: abs, min, max, floor, ceil, round, random, sqrt, pow, sin, cos,
tan, atan2, clamp, lerp
String: split, join, trim, upper, lower, replace, starts_with, ends_with,
char_at, substring
Conversion: int, float, string, bool
Console: log, debug, warn
Timer: delay
Also adds ExprStatement support for top-level expressions (log, push, etc).
110 tests, 0 failures.