`any_to_string` runs `type := type_of(val)`; for an `.any` operand
`type_of` lowers to `struct_get(val, 0)` to read the Any's tag. At
runtime a first-class Type value is the aggregate `{ tag=.any, value=tid }`
so the read succeeds, but the comptime interpreter stores a Type as a bare
`.type_tag(tid)` and the comptime `struct_get` arm had no case for it — it
raised `CannotEvalComptime`, which `runComptimeSideEffects` swallowed into
`void_val`, truncating the `#run` while still building with exit 0.
- interp.zig: comptime `struct_get` handles a `.type_tag(tid)` base by
mirroring the runtime Any-Type layout (field 0 -> `.any` tag, field 1 ->
the type id), so `type_of` of an Any-held Type evaluates as it does at
runtime and execution continues.
- emit_llvm.zig: `runComptimeSideEffects` no longer swallows a side-effect
bail; it prints a loud diagnostic and sets `comptime_failed`
(-> error.ComptimeError, non-zero exit), matching the const-init path.
A truncated `#run` can no longer ship a successful build.
Regression: examples/0613-comptime-print-any-type.sx (all five lines print,
exit 0). Resolves issue 0096.
