* AstGen: fix emitting `store_to_inferred_ptr` when it should be emitting
   `store` for a variable that has an explicit alignment.
 * Compilation: fix a couple memory leaks
 * Sema: implement support for locals that have specified alignment.
 * Sema: implement `@intCast` when it needs to emit an AIR instruction.
 * Sema: implement `@alignOf`
 * Implement debug printing for extended alloc ZIR instructions.