🎨 Palette: Improve accessibility of pairing card

[yuga-hashimoto]

💡 What
Added Modifier.semantics(mergeDescendants = true) to the Row holding the title and the Devices icon in PairingRequiredCard.kt.

🎯 Why
To prevent screen readers like TalkBack from redundantly announcing both the decorative icon and the title separately. Encapsulating them into a single focus bounds ensures a cohesive reading.

📸 Before/After
No visual changes.

♿ Accessibility
Improves screen reader behavior by eliminating redundant and fragmented navigation announcements for the pairing required card header.

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PR created automatically by Jules for task 2257461732623023490 started by @yuga-hashimoto

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