Refactor PreviewScreen to use lambdas for deferred state reading

[temcguir]

This PR refactors PreviewScreen to use lambda providers (() -> T) instead of passing raw UI state values down the composable tree.

It also utilizes derivedStateOf to tightly scope high-frequency state reads (like elapsed recording time and low-light boost active state) to the specific child composables that need them. This dramatically reduces unnecessary recompositions of the entire PreviewScreen wrapper, significantly improving UI performance during capture.

Note: This PR is stacked on top of PR 519 (temcguir/disable_animations).

[gemini-code-assist]

Code Review

This pull request refactors PreviewScreen.kt to optimize recompositions by introducing deferred state providers and wrapping slot lambdas in remember blocks. The review feedback highlights a critical potential NullPointerException in Compose Previews due to a non-null assertion on zoomController, a performance issue in elapsedTimeDisplayLambda causing excessive recompositions, and outdated KDoc documentation for ElapsedTimeText.

[temcguir]

@gemini-code-assist The suggested fixes for the NullPointerException in the ZoomStateManager preview fallback, the deferred state read leak in the elapsedTimeDisplayLambda, and the updated KDoc for ElapsedTimeText have all been implemented. PTAL!

[gemini-code-assist]

Code Review

This pull request refactors PreviewScreen and its sub-composables to use deferred state reads via lambda providers (e.g., captureUiStateProvider), isolating recompositions and improving performance. Feedback on these changes highlights a potential bug where capturing the provider directly inside derivedStateOf blocks can lead to stale lambda references; using rememberUpdatedState is recommended to resolve this. Additionally, the reviewer noted a need to update the KDoc parameter name in CaptureScreenComponents.kt and to add missing KDoc documentation for the FlashModeIndicator composable in QuickSettingsComponents.kt to comply with the repository's style guide.