fix: scene not initialized properly when tab not focused

[dwelle]

• fixes a regression introduced during rewrite for npm package: by moving to promise-based initialization, we've been mistakenly been early-resolving in late-initialization scenarios which ended up not initializing the scene properly
• also fixed an issue where late initialization wasn't prompting due to onChange callback being called early and overriding localStorage with empty data

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[ad1992]

LGTM