What changed

Fixes an occasional crash on the dashboard reported in Google Play Console for v5.1.0. Triggered when multiple Bluetooth devices match the same profile — most common with non-IRK profiles where the legacy signal-quality fallback assigns ambient pods to a user profile.

Technical Context

• Root cause: OverviewScreen keyed the profiled-device LazyColumn on profileId alone (introduced in 77ea3121). DeviceMonitor deliberately keeps multiple PodDevice entries per non-IRK profile (DeviceMonitor.kt:104–106), so the uniqueness assumption was wrong and Compose threw IllegalArgumentException from LayoutNodeSubcompositionsState.subcompose.
• The signature is dominated by users navigating in/out of Overview because Navigation3's NavDisplay wraps each screen in AnimatedContent; the extra remeasure passes during screen transitions widen the duplicate-key window.
• Fix is UI-side only: keys stay profiled:<pid> for the common single-device case (preserving item state across recompositions and animations) and only disambiguate as profiled:<pid>:<identifier> when the current list actually contains a collision. Same defensive treatment applied to unmatched devices, where the previous ?: hashCode() fallback could collide structurally for data-class-equal PodDevice snapshots.
• DeviceMonitor merge logic is unchanged — keeping multiple non-IRK matches visible is documented as intentional.
• Out of scope (rare edge cases hidden by the crash): duplicate cards share expansion state (userExpansionOverrides is keyed by profileId) and may visually swap order between scans.