[bug] codegen E2010: wasm local type conflict when i64 return immediately follows raise in try body

[Nymphium]

Discovered nexus-dvr6.6 batch10. Specific shape:

let r = try
  raise SomeExn(...)
  return 0  // unreachable but typechecks
catch _ -> 1
end

triggers wasm codegen 'variable "__t2" has conflicting wasm local types' E2010. Sidestepped by moving the unreachable return past end.

Likely the LIR slot allocator doesn't handle the unreachable-after-raise path correctly: __t2 gets two type registrations from different branches that diverged via raise.

Acceptance: the inline shape compiles cleanly without local-type conflict.