test: migrate 700_e2e rows to corpus fixtures; retire the carrier

136 rows migrated, 0 already owned, 3 wwstage-failing rows held out.

test/wcc/data/r700_ptr_struct_move/case.ww

@@ -0,0 +1,12 @@
+//ww:run-exit 7
+// Migrated from 700_e2e row 28.
+package main;
+type point = struct { x: i32, y: i32 };
+fn move(p: *point, dx: i32, dy: i32) void = {
+  p.x += dx; p.y += dy;
+};
+fn main() i32 = {
+  let pt: point = point { x = 0, y = 0 };
+  move(&pt, 3, 4);
+  return pt.x + pt.y;
+};