- references to other instances are no longer flagged
- special handling for genvars to avoid flagging and modport scoping
- interface inlining visits expressions in declarations
- Scoper has interface for removing entries

- don't keep unused template modules even if they are fully-specified
- don't reduce modules with unbound type parameters

The interface conversion no longer substitutes parameters immediately,
instead fully scoping modports and allowing hierarchical constants to be
resolved separately. This fixes an issue where struct parameters could
lose their type information during substitution. The conversion also now
handles renaming references to the module or interface top-level scope.

- scoper item injection can no longer affect generate scoping
- cast conversion injects functions into the top level when possible
- cast conversion considers loop variables to be local
- `else if` generate blocks are still scopes at the current level

- substitute enum item values directly into usage sites rather than
  creating synthetic localparams
- substitution handles shadowing of expressions in enum item values
- disconnected scopes can reference conflicting enum items

- convert loops with no or many incrementations
- restrict AST node to only contain traditional initializations
- parser elaborates for loop decls into a synthetic block
- decl list codegen is now specific to parameter decl lists
- update jump conversion special cases for new representation
- first experiments with bimapM

Disabling the package item injection routine used in the enum conversion
when there were no items to inject exposed cases where conversions would
generate duplicate declarations. The hierarchical constant and param
type conversions were trivially affected. The package conversion could
inject class items within a generate region and then re-inject them
outside of that generate region. The package conversions now uses an
upgraded generate region flattening utility to ensure injected class
items are seen. This also includes coverage for a conflict which
occurred even without the enum conversion change.

- fix int type conversion not visiting function return type expressions
- add node-based traversal for decls visiting top level types and exprs
- explicit expr and type recursion in package ident resolution
- expose mapBothM traversal helper
- avoid double-visiting of decl types in certain conversions

- avoid packing memories used with read mem tasks
- fix detection of $readmem[hb] in logic conversion

- standardize number casting
- fix extension of casts of unsized literals to 32 bits

- support for additional assignment statements in loop initializations
- greatly improved error messaging in these contexts
- decl parser takes in the ending token; significant related refactoring
- pass through elaboration system tasks
- removed non-blocking assignment operator precedence hack
- preliminary nosim test suite for features unsupported by iverilog

- new net decl to replace net pseudo-type
- support nets with complex base types, including typenames
- support var declaration type prefix for all data types
- support var as lone type shorthand
- refactor AST representation of strengths
- traversal helpers for treating nets as variables
- use decl traversals where appropriate