The `fixed_scope_idx` field has been removed from `Binder` and
`Environment`. This field was used to enforce immutability on certain
scopes during binding.
The logic for handling the immutability of the root scope (scope 0) has
been moved and refactored. Now, during the `Environment::new` bootstrap
phase, the addresses within the RTL scope (scope 0) are directly
translated from `Address::Local` to `Address::Global`. This ensures that
the Binder inherently treats these as global and immutable without
needing an explicit `fixed_scope_idx` check.
The `Binder::bind_root` signature has been updated to reflect this
change by removing the `fixed_scope_idx` parameter. Consequently, tests
and other usages of `bind_root` have been adjusted.
This change simplifies the binding process by centralizing the
immutability handling to the environment setup phase, making the
Binder's logic cleaner.
Brummel
35f5ea0db3