feat: refactor/support tuple structs and enums

[bbaldino]

Lots here, including some major code reorganization. Main bulk of the changes are to support enums and tuple structs.

[Copilot]

Pull Request Overview

This PR refactors the codebase to support enums and tuple structs by reorganizing core implementations, improving the APIs used for reading and writing, and updating field handling to better support non-standard struct layouts. Key changes include:

• Refactoring field-related functions to accept &syn::Member instead of &syn::Ident.
• Updating module visibility and renaming receiver types in the derive implementations.
• Cleaning up legacy code and reorganizing helper functions for improved maintainability.

Reviewed Changes

Copilot reviewed 32 out of 32 changed files in this pull request and generated no comments.

File	Description
impl/src/model_types.rs	Updated field parameter types and removed legacy assignment generation code to improve tuple struct support.
impl/src/lib.rs	Exposed the syn_helpers module as pub(crate) and updated derive dispatch logic for receiver types.
impl/src/code_gen/*	Reorganized generation logic into dedicated read and write modules and updated receiver types for enums and structs.
Notes.md	Updated design notes documenting attribute precedence and reordering logic for ParselyRead.

Comments suppressed due to low confidence (3)

impl/src/model_types.rs:242

• Changing the field parameter from &syn::Ident to &syn::Member improves support for tuple struct fields, but please ensure consistent usage and clear documentation across the codebase.

pub(crate) fn to_read_map_tokens(&self, field_name: &syn::Member, tokens: &mut TokenStream) {

impl/src/lib.rs:6

• Exposing the 'syn_helpers' module as pub(crate) increases its visibility; please verify that this change aligns with the intended encapsulation boundaries of the project.

pub(crate) mod syn_helpers;

impl/src/model_types.rs:22

• [nitpick] The removal of the custom assignment generation method from TypedFnArgList simplifies the type's interface; please confirm that any necessary specialized assignment logic is now handled appropriately in a different location.

// Removed assignment generation method