feat: create @zag-js/lit (WIP)

[nikparo]

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📝 Description

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WIP work on creating a @zag-js/lit framework. Adds packages/frameworks/lit and examples/lit-ts, and adapts e2e/ testing suite to optionally work with shadow-dom.

This PR is only open for visibility and comments, it's not ready to be merged.

NOTE: Video is from my dev/lit branch that combines several other branches, including:
#2694
#2697
#2695

⛳️ Current behavior (updates)

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🚀 New behavior

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Screen.Recording.2025-09-09.at.12.46.26.mov

💣 Is this a breaking change (Yes/No):

📝 Additional Information

Related discussion threads:
#2681
#1210

Thank you @gperdomor for your work on #2608

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Latest commit: 5b51fc9

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Project	Deployment	Preview	Updated (UTC)
zag-nextjs	Ready	Preview	Sep 9, 2025 9:57am
zag-solid	Ready	Preview	Sep 9, 2025 9:57am
zag-svelte	Ready	Preview	Sep 9, 2025 9:57am
zag-vue	Ready	Preview	Sep 9, 2025 9:57am
zag-website	Ready	Preview	Sep 9, 2025 9:57am

[gperdomor]

Amazing job @nikparo… I hope that this can be merged soon ❤️