Dependencies: update Compose BOM 2026.06 to 2026.08 / Compose 1.12 after U0/U1 baseline

[MrFr3di]

Objective

Update the Compose BOM from the repository's 2026.06.00 baseline to the stable August 2026 Compose line (Compose UI/runtime/foundation 1.12 family; staged as BOM 2026.08.00 in #190) as an isolated UI-runtime dependency package.

Owner under #179. #190 remains a compatibility probe only.

Critical sequencing rule

Compose runtime/focus/layout behavior can affect the same surfaces currently being characterized by U0/#189. Therefore this dependency must not be merged before U0 runtime evidence and U1 correction are accepted. Prefer landing after #178/M0 too, so the stabilization/measurement baseline is frozen before UI-runtime movement.

Scope

• Compose BOM/dependency line only;
• compilation adaptations strictly required by stable API movement;
• preserve Lounge product visuals and geometry unless a separate issue owns a proven correction;
• preserve focusRestorer() / Navigation3 ownership;
• no experimental Compose Styles/SlotTable/runtime flags merely because the new version exposes them;
• no mass @Stable/remember/derivedStateOf cleanup without profiling.

Acceptance

• resolved Compose artifacts align to the intended stable BOM/family with no accidental mixed runtime/ui versions;
• host Compose/unit tests green;
• accepted U1 rail/content geometry remains unchanged;
• Home/Channels/Guide/Search/Settings D-pad/focus regression green on canonical API36;
• API26 compatibility evidence where applicable;
• representative 1080p + 720p display configurations reuse the same canonical API36 AVD;
• no third AVD;
• Macrobenchmark/frame evidence is collected before claiming performance improvement;
• no experimental feature becomes an alpha dependency by default.

Non-goals

• Lounge redesign;
• U0/U1 root-cause fix;
• Navigation3/Media3/Paging/Room/toolchain bundle;
• experimental Compose Styles;
• speculative performance annotations.

Official references

• https://developer.android.com/jetpack/androidx/versions/stable-channel
• https://developer.android.com/jetpack/androidx/releases/compose-runtime