fix: strengthen Options interface

[antongolub]

• Tests pass
• Appropriate changes to README are included in PR

[Copilot]

Pull Request Overview

This PR strengthens the Options interface by converting it from an interface with optional properties to a more type-safe structure using Partial<> and introducing new helper types for better type safety and code organization.

• Restructures the Options interface to use Partial<> wrapper for all properties
• Introduces new type definitions (Defaults, NormalizedOpts, Snapshot) for better type organization
• Adds explicit type annotations to function parameters that previously relied on default values

Reviewed Changes

Copilot reviewed 3 out of 5 changed files in this pull request and generated 3 comments.

File	Description
src/core.ts	Refactors Options interface structure, adds new type definitions, and improves type safety with explicit parameter typing
build/core.cjs	Updates compiled JavaScript to reflect parameter name changes from the TypeScript refactor
.size-limit.json	Adjusts bundle size limits to accommodate the type system changes

[Copilot]

The Defaults interface excludes 'quote' from the Required wrapper but 'quote' is included in the defaults object at line 144. This inconsistency could lead to type errors where 'quote' is expected to be always present in defaults but typed as optional.

Suggested change

	extends Required<Omit<Options, 'ac' | 'cmd' | 'cwd' | 'prefix' | 'postfix' | 'delimiter' | 'halt' | 'input' | 'quote' | 'signal' | 'store' | 'timeout'>> {
	extends Required<Omit<Options, 'ac' | 'cmd' | 'cwd' | 'prefix' | 'postfix' | 'delimiter' | 'halt' | 'input' | 'signal' | 'store' | 'timeout'>> {
	quote: typeof quote

[Copilot]

Changing from Partial<Options> to Options makes the type constraint more restrictive. Since Options is now Partial<{...}>, users may be required to provide properties that were previously optional, potentially breaking existing code.

Suggested change

	<O extends Options = Options, R = O extends { sync: true } ? Shell<true> : Shell>(opts: O): R
	<O extends Partial<Options> = Partial<Options>, R = O extends { sync: true } ? Shell<true> : Shell>(opts: O): R

[Copilot]

Removing Partial<> wrapper from Omit<Options, 'sync'> makes this parameter less flexible. Since Options properties are now all optional via Partial<>, this change may require users to provide more properties than necessary for the sync shell.

Suggested change

	(opts: Omit<Options, 'sync'>): Shell<true>
	(opts: Partial<Omit<Options, 'sync'>>): Shell<true>

[antongolub]

Superseded by other refactorings