[design-qa][P1] Toasts: the wrong black, a shadow, a second host under the tab bar, 88 dp above nothing on pushed screens

[cestercian]

Part of the Sep-2026 designer's-eye QA of the 138 "Artistant iOS Light" screens (theme T16, category token; epic #161). Full report with evidence and per-screen coverage: docs/DESIGN_QA_2026-09.md; the per-section appendices under docs/design-qa/ carry the code excerpts.

Why it matters. The capsule paints ink with a 12 dp shadow where the palette names dark and the design is flat; the press kit mounts its own host that fires under the tab bar; the root host pads for a tab bar that pushed screens do not show.

Fix direction. One host, dark fill, no shadow, bottom padding driven by whether a bar is actually visible.

Findings (3: P1 ×2, P3 ×1)

• F-CC-06 (P3) — Toast is drawn on the wrong black and casts a shadow on a flat design
  • Screens: 77 and every toast
  • Where: designsystem/component/Toast.kt:133-135
  • Fix: background(colors.dark), drop the shadow (a hairline in lineStrong if separation is needed).
• F-SH-03 (P1) — Every toast raised from a pushed screen floats 88dp above nothing
  • Screens: 77, and every screen that raises a toast
  • Where: navigation/ArtistantNavHost.kt:198-210; designsystem/component/Toast.kt:82, :103; navigation/ClientTabsScaffold.kt:216-217; navigation/ArtistTabsScaffold.kt:166-167
  • Fix: hoist the "is the tab bar actually drawn" fact out of the scaffolds (the showBottomBar boolean) and feed the host that, not the gate; and use bottom = rather than vertical =.
• F-PK-01 (P1) — Delete the press kit's own toast host; it fires under the tab bar
  • Screens: 23, 87, 76
  • Where: feature/epk/EpkScreen.kt:267; peer navigation/ArtistantNavHost.kt:198-210; designsystem/component/Toast.kt:83
  • Fix: route statusNote through the root ToastVm and delete the in-package host (the migration CLAUDE.md already calls outstanding).

Acceptance

• Every finding above is closed on the cited lines (or refuted in a comment with the reason).
• ./gradlew :app:assembleDebug, :app:testDebugUnitTest and :app:lintDevDebug green.
• The screens listed above walked on the artistant AVD with the debug harness (RELEASE.md §10) and the fix confirmed visually — this audit was code-grounded, not device-walked.