Add runner type to ClassicAllocator

[prozacchiwawa]

Summary

• add an associated runner type to ClassicAllocator, constrained to clone and dereference to TRunProgram
• use Rc<dyn TRunProgram> for both existing allocator implementations
• update allocator-generic classic compiler functions to accept the associated runner type
• make affected test calls explicit where associated-type inference prevents runner coercion

Testing

• cargo check --all-targets
• cargo test --lib tests::classic::stage_2 (17 passed)
• cargo test --lib -- --skip compile_performance_suite (705 passed, 1 ignored, 1 filtered)
• rustfmt --edition 2021 --check on all changed Rust files

The unfiltered library suite reached only the existing long-running compile_performance_suite; it was stopped after the other tests completed and then rerun successfully with that performance test excluded.