Fix status bar icon contrast in bookmark dialogs

[arpitagarwal1301]

Description

Fixes the status bar icon contrast when opening Bookmarks from a user file. Light-background themes now use dark status bar icons, while dark-background themes continue using light icons.

Fixes #2127

Testing Instructions

1. Use a paid account with an uploaded file.
2. Select a light-background theme.
3. Open Profile > Files, select a file, and tap Bookmarks.
4. Verify that the status bar icons are dark and readable.
5. Repeat with a dark-background theme and verify that the icons remain light.
6. Dismiss the dialog and verify that the previous status bar appearance is restored.

Screenshots or Screencast

Not included because the affected Cloud File flow requires a paid account with uploaded content.

Checklist

• Added an entry to CHANGELOG.md.
• Ran ./gradlew spotlessCheck.
• Considered automated coverage; the existing unit-test setup does not expose Android system-bar rendering.
• No strings, Compose UI, analytics schema, or migrations changed.

Validation

• git diff --check
• ./gradlew spotlessCheck
• :modules:features:player:testDebugUnitTest — 77 tests, 0 failures, 0 skipped

[CLAassistant]

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[geekygecko]

Thanks for the contribution. Would you be able to sign the Contributor License Agreement?

[wpmobilebot]

Version 8.18 has now entered code-freeze, so the milestone of this PR has been updated to 8.19.