feat: Support isolated nested state via StateScopeProvider

[quynhtrang0309]

This PR introduces the StateScopeProvider component, allowing developers to create isolated state scopes within their React application.

Key Changes:

1. StateScopeProvider: A new component that generates a unique scope ID (via useId) and provides it to its children via StateScopeContext. It also renders an internal AutoRootCtx to manage the roots for that specific scope.
2. Scope-Aware useDataContext: The useDataContext hook now reads the current StateScopeContext. If a scope ID is present, it prefixes the context name (e.g., ":r1:/my-store"), ensuring data isolation.
3. Duplicate Mount Check: The createRootCtx factory now includes the scope ID when checking for duplicate root mounts, preventing false positives when the same store is used in different scopes.

Usage:

<AutoRootCtx>
  {/* Global Scope */}
  <App />
  
  <StateScopeProvider>
     {/* Isolated Scope - Stores here are independent of Global Scope */}
     <Feature />
  </StateScopeProvider>
</AutoRootCtx>

Testing:

• Added tests/createAutoCtx.nested.test.tsx which confirms that state updates in an outer scope do not affect the inner scope and vice-versa.
• Validated that existing global state behavior remains unchanged.

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PR created automatically by Jules for task 12691107722258462697 started by @quynhtrang0309

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[Copilot]

Pull request overview

Adds first-class “state scoping” to react-state-custom so nested subtrees can run isolated instances of the same stores without cross-talk, while keeping existing global behavior unchanged when no scope is present.

Changes:

• Introduces StateScopeProvider to create an isolated scope and mount a scope-local AutoRootCtx.
• Makes useDataContext scope-aware by prefixing context names with the active scope ID.
• Updates createRootCtx duplicate-mount checks to include scope in the key; adds a nested-scope isolation test and updates docs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tests/createAutoCtx.nested.test.tsx	Adds a regression test validating outer/inner scope isolation.
src/state-utils/ctx.ts	Adds StateScopeContext and scope-aware context name resolution in useDataContext.
src/state-utils/createRootCtx.tsx	Includes scope in duplicate mount / missing-root checks.
src/state-utils/createAutoCtx.tsx	Adds StateScopeProvider (scope ID + scoped AutoRootCtx).
README.md	Documents isolated state usage via StateScopeProvider.
API_DOCUMENTATION.md	Adds API reference section for StateScopeProvider.

[Copilot]

useCtxState’s mount-check effect depends on ctxMountedCheck.has(scopedCtxName), which won’t re-run/cleanup when the Root becomes mounted because the Set mutation doesn’t trigger a re-render. This can cause a delayed console.error even when the Root mounts successfully. Use a stable dependency like scopedCtxName (and re-check inside the effect) so the timeout can be cleared when appropriate.

[Copilot]

The README example imports StateScopeProvider from react-state-custom, but it is not currently re-exported from the package entrypoint (src/index.ts). Consumers following this snippet will get a missing export error; please re-export StateScopeProvider from the public index (or adjust the docs if it’s intentionally internal).

Suggested change

	import { AutoRootCtx, StateScopeProvider } from 'react-state-custom'
	import { AutoRootCtx } from 'react-state-custom'
	// Example of a custom scope provider component wrapping an isolated part of your app.
	function StateScopeProvider({ children }: { children: React.ReactNode }) {
	return <>{children}</>
	}

[vothanhdat]

@copilot re-export it

[Copilot]

@vothanhdat I've opened a new pull request, #22, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated no new comments.