foreach does not work correctly for Int as coins value serialization

[Gusarich]

The function below compiles successfully but throws 9 exit code in runtime.

fun f(): Int {
    let m: map<Int, Int as coins> = emptyMap();
    m.set(1, 100);
    m.set(2, 200);

    let sum: Int = 0;
    foreach (k, v in m) {
        sum += k + v;
    }

    return sum;
}

This is due to the fact that there is no coins serialization handling in foreach codegen:

• tact/src/generator/writers/writeFunction.ts

  Lines 287 to 295 in 9156921

  	if (t.value === "Int") {
  	let vBits = 257;
  	let vKind = "int";
  	if (t.valueAs?.startsWith("int")) {
  	vBits = parseInt(t.valueAs.slice(3), 10);
  	} else if (t.valueAs?.startsWith("uint")) {
  	vBits = parseInt(t.valueAs.slice(4), 10);
  	vKind = "uint";
  	}

• tact/src/generator/writers/writeFunction.ts

  Lines 375 to 383 in 9156921

  	if (t.value === "Int") {
  	let vBits = 257;
  	let vKind = "int";
  	if (t.valueAs?.startsWith("int")) {
  	vBits = parseInt(t.valueAs.slice(3), 10);
  	} else if (t.valueAs?.startsWith("uint")) {
  	vBits = parseInt(t.valueAs.slice(4), 10);
  	vKind = "uint";
  	}