Function jit_array_push_local 

#[unsafe(no_mangle)]
pub extern "C" fn jit_array_push_local(
    array_bits: u64,
    value_bits: u64,
) -> u64

Push a value into an array in-place, mutating the existing JitArray. Returns the same array bits (the JitAlloc pointer doesn’t move; JitArray handles realloc internally). This is O(1) amortized vs O(n) for jit_array_push_elem which copies all elements. Used by ArrayPushLocal opcode for x = x.push(val) optimization.