Add code generation for array

codegen/array/snippets/copy_capped

@@ -0,0 +1,16 @@
+  if (!src || !dst) {{
+    return;
+  }}
+
+  wapp_{Tlower}_array_clear(dst);
+
+  {T} *item;
+  u64 to_copy = src->count < dst->capacity ? src->count : dst->capacity;
+  for (u64 i = 0; i < to_copy; ++i) {{
+    item = wapp_{Tlower}_array_get(src, i);
+    if (!item) {{
+      continue;
+    }}
+
+    wapp_{Tlower}_array_append_capped(dst, *item);
+  }}