improve iOS accessibility and modern SwiftUI interaction patterns

[austin-smith]

Problem

There are several iOS interaction and accessibility gaps in the current UI:

• BitDream/Views/iOS/Settings/iOSSettingsView.swift:115 uses onTapGesture for accent color selection.
• BitDream/Views/iOS/Settings/iOSSettingsView.swift:161 uses onTapGesture for app icon selection.
• BitDream/Views/iOS/iOSTorrentDetail.swift:270 and nearby rows rely on .foregroundColor(.gray) and fixed-size text patterns that will age poorly with Dynamic Type and accessibility settings.

Goal

Bring these areas in line with modern SwiftUI interaction and accessibility expectations, especially for VoiceOver, Dynamic Type, and semantic styling.

Acceptance Criteria

• Selectable rows in iOS settings use button-based interaction instead of tap gestures.
• VoiceOver semantics improve for interactive settings rows.
• Detail content avoids unnecessary hard-coded gray styling where semantic foreground styles are more appropriate.
• Fixed-size typography is reviewed and adjusted where it harms accessibility scaling.
• Behavior remains visually consistent with the current product direction while becoming more accessible and maintainable.