feat: Add React interop adapter

[TudorGR]

Implements WrapForReact() to enable seamless use of Rimmel components inside React applications.

Features:

• Converts React props to BehaviorSubject observables
• Maintains Rimmel's no-re-render reactive model
• Proper lifecycle management and cleanup
• React as optional peer dependency (zero bloat for non-React users)

Usage:

const ReactCounter = WrapForReact(RimmelComponent);
<ReactCounter externalCounter={reactState} />

Example included at react-interop demonstrating bidirectional reactivity.

Closes #71

[bolt-new-by-stackblitz[bot]]

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[TudorGR]

I addressed both concernes:

1. Lazy observable creation Used Proxy pattern to only create BehaviorSubjects when components actually access props—no more unnecessary subjects for unused props.

2. Dependency isolation Moved React adapter to separate @rimmel/in-react package. Main Rimmel package no longer pulls in React as a peer dependency.

Migration for users:

npm install @rimmel/in-react

import { WrapForReact } from '@rimmel/in-react';

Testing:

• Package builds successfully
• Example project verified working
• No breaking changes for non-React users