feat: Add sync module, refactor core module, update build

[mitsuki31]

Overview

This branch reshapes several parts of the project: the core module is reorganized, type definitions are corrected, a synchronous variant of the library is introduced, and the build process gains a postbuild cleanup phase. Documentation and tests have been adjusted to match the new structure. The goal is to tighten the internal design while making the API surface more predictable for users and Intellisense.

Introduce New Sync Module

Synchronous version of LSFND has been implemented. Users can imports them from /sync submodule of lsfnd. For example:

import { ls, lsTypes } from "lsfnd/sync";
// Or:
const { ls, lsTypes } = require("lsfnd/sync");

Changes Made

• Updated the README to reflect the current state of the project.
• Introduced a postbuild step and modified the production TypeScript configuration to preserve comments in transpiled output.
• Added the scripts/postbuild module, including the removeMultilineCommentsAfterUseStrict utility.
• Removed the old API type implementations from types/index.
• Added postbuild script to package.json.
• Added full test coverage for the new lsfnd-sync module, including CJS and ESM variants.
• Updated existing tests and test scripts to accommodate the new modules.
• Added the lsfnd-sync module, a synchronous counterpart to the core module with code adapted appropriately.
• Reorganized the core module, moving utilities into a dedicated utils module and constants into a new constants module.
• Refined the core logic by fixing unresolved types for match and exclude, enhancing resolveOptions to accept RegExp, and adding a special case for LS_A when passed 0.
• Improved internal type definitions, correcting the LsTypesValues type, strengthening ResolvedLsOptions, and removing redundant casts.
• Made all ls* functions to guaranteed accept both string keys and numeric values from lsTypes, throwing errors on unknown values.

Impact

The internal structure becomes clearer and easier to maintain. Type safety improves across the board, reducing silent inconsistencies and making the API more predictable. The synchronous module fills a long-standing gap for environments where async behavior is less desirable. Tooling improvements ensure the output retains necessary comments while removing module-generated clutter. Developers will get cleaner IntelliSense results with better documentation visibility.

Summary

This update pulls several threads together: reorganized internals, corrected types, a new synchronous API, an improved build pipeline, and refined tests. The project becomes more coherent without changing its fundamental behavior.