Implement dark mode for unauthenticated Settings

[anamhira47]

Summary

Enables system dark mode for SweepAlert and updates the unauthenticated Settings cluster so text and surfaces remain readable when the device uses a dark appearance.

Previously, dark mode was blocked in two places:

• SweepAlertSwiftApp forced .preferredColorScheme(.light)
• Info.plist set UIUserInterfaceStyle to Light

This PR removes both locks so the app follows the system appearance.

Changes

• Remove forced light mode in SweepAlertSwiftApp.swift and Info.plist
• Adaptive brand tokens for sweepInk, sweepMuted, and card strokes using dynamic UIColor providers
• Semantic text colors in SettingsScreen and SignedOutPanel (.primary / .secondary) for the unauthenticated Account and Crew sections
• Revyl config added for remote iOS builds (apps/ios-sweep-alert/.revyl/config.yaml)

Device verification

Before (light mode — unauthenticated Settings):

• Account section shows “Sign in to sync alerts” with Log in CTA
• Crew section shows locked “Sign in to manage cars” state

After (dark appearance enabled on device):

• Remote Revyl build succeeded and installed on device
• With system dark appearance enabled, the signed-out map UI and bottom panel adopt dark surfaces
• Settings overlay uses systemGroupedBackground / systemBackground and semantic text colors for dark readability

Validation notes:

• revyl device instruction successfully opened unauthenticated Settings on device
• Automated dark-appearance toggling on the remote simulator was flaky; screenshots above capture light Settings baseline and dark-mode app surfaces after enabling dark appearance

Test plan

• Remote Revyl iOS build passes
• Unauthenticated Settings opens from signed-out gear button
• Light-mode Settings baseline captured
• Dark appearance surfaces verified on signed-out map UI after system theme change

  

[revyl-dev]

Preview builds for 76e90e53.

Build Target	Status	Details	Updated (UTC)
SweepAlert Swift (iOS)	Ready		2026-06-28 05:31

Validation

Check	Status	Details	Updated (UTC)
Proof of changes	Failed		2026-06-28 05:37

What we exercised

We launched the app with the system Dark Mode appearance enabled. We verified that the bottom signed-out banner on the main map uses appropriate dark surfaces. Finally, we opened the unauthenticated Settings screen via the gear icon and confirmed that the background, card panels, and text labels render perfectly with dynamic dark-mode colors instead of being forced into light mode.

Revyl debug · proof diagnostics (internal)

• Proof of changes — failed · stage: Ready
  • dispatch: submitted → scm-adaptive-report_codex-168d-staging (run 2ff85937-403)
  • device run: 023559e4-88f
  • summary: Adaptive proof needs attention. Open the Revyl report for the failed step details.
  • session