fix: Builder parser does not strip falsey style values

[liamdebeasi]

Description

The Builder JSON parser currently strips out falsey style values (I.e. padding: 0). The original motivation for this was to cut down on the amount of CSS generated with codegen in Builder. However, our codegen process has improved since then where this is not a big problem anymore.

More importantly, stripping falsey values is causing functional changes to the code because we make the assumption that a value of 0 is the same as not having the CSS declaration to begin with which is not always true. For example, we remove values such as flex-shrink: 0. However, the default value for flex-shrink is 1.

Another example can be seen here: https://codepen.io/liamdebeasi/pen/gbOrgJm

In the first block #text has z-index: 0 which causes it to show on top of the square. In the second block ,#text does not have z-index: 0 which causes it to show below the square.

This PR resolves the issue by removing logic that removes falsey CSS values.

For added context, this logic was originally added via a PR to Mitosis, but this PR was a port from another repo.

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[changeset-bot]

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Latest commit: f585cd0

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[nx-cloud]

View your CI Pipeline Execution ↗ for commit 5212ea4.

Command	Status	Duration	Result
nx run-many --target test	✅ Succeeded	4m 41s	View ↗
nx e2e @builder.io/e2e-app	✅ Succeeded	1m 6s	View ↗
nx run-many --target build --exclude @builder.i...	✅ Succeeded	3m 41s	View ↗
nx build @builder.io/mitosis-site	✅ Succeeded	2m 22s	View ↗

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☁️ Nx Cloud last updated this comment at 2025-02-21 16:00:32 UTC

[kylefowler]

ship it