Refactor parse utilities into dedicated modules

[leynos]

Summary

• split parse utilities into params, outputs, and type_expr modules
• move delimiter helpers into token_utils and document error helpers
• add targeted tests for parameter, output, and type expression parsing

Testing

• make lint
• make test

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https://chatgpt.com/codex/tasks/task_e_68a139f69b648322a01bb05bb039300d

Summary by Sourcery

Restructure the parsing utilities by splitting them into dedicated modules for parameters, outputs, and type expressions; centralize common token and delimiter helpers in token_utils; remove the old type_parsing module; and add comprehensive tests for parameter, output, and type expression parsing.

Enhancements:

• Split the parse_utils directory into separate params, outputs, and type_expr modules
• Move trivia detection and delimiter helper logic into token_utils
• Update parse_utils exports to use the new modular functions

Tests:

• Add targeted tests for parsing parameters, outputs, and type expressions covering various edge cases

Chores:

• Remove the obsolete type_parsing module