`accessibility_trait_for_button` false positive with `if #available` check

New Issue Checklist

• I've Updated SwiftLint to the latest version.
• I've searched for existing GitHub issues.

Bug Description

Using . isToggle in an app that supports a version before iOS 17 requires an if #available, which breaks this lint rule. Example:

struct ContentView: View {
    var body: some View {
        Text("Hello, World!")
            .onTapGesture {
                print("foo")
            }
            .accessibilityAddTraits({
                if #available(iOS 17, *) {
                    [.isToggle, .isButton]
                } else {
                    .isButton
                }
            }())
    }
}

Mention the command or other SwiftLint integration method that caused the issue. Include stack traces or command output.

$ swiftlint lint --strict
Linting Swift files in current working directory
Linting 'TestApp.swift' (2/2)
Linting 'ContentView.swift' (1/2)
~/Desktop/test/test/ContentView.swift:12:9: error: Accessibility Trait for Button Violation: All views with tap gestures added should include the .isButton or the .isLink accessibility traits (accessibility_trait_for_button)
Done linting! Found 1 violation, 1 serious in 2 files.

Environment

• SwiftLint version:

$swiftlint version
0.63.1

• Xcode version:

$xcodebuild -version
Xcode 26.2
Build version 17C52

• Installation method used: Homebrew
• Configuration file:

# Ran in minimal setup to test
opt_in_rules:
  - accessibility_trait_for_button

Are you using nested configurations? No

Start with the accessibility_trait_for_button rule and reproduce the report using the provided Swift example and minimal opt_in_rules configuration. Trace how the if #available expression is analyzed; done means the valid .isButton trait in that branch no longer produces a false positive, with coverage for the reported case.