feat(ui): TASK 42 top bar redesign — one Record-or-Stream surface (2026-09-22)

The bar now renders ONE surface from the FIRST decision the creator makes —
Record or Stream — with each world being the whole bar. Creator directive:
"I wrote the fucking thing and I still can't figure-out how to do stuff",
"forget this one dog plan bullshit". OBS/streaming-tool reference for the
one-surface paradigm: https://obsproject.com (single mode toggle + context
actions) — cited per spin-guard habit; the go-live/test pattern follows
CEV (https://cev-desktop.aSean.xyz) precedent.

- Mode: single segmented REC|ON-AIR switch (SegmentToggle/SegmentLabel in
  Themes/Controls.xaml); radio-exclusive world selection, one tap to flip.
- Record world: switch + Start Recording, zero YouTube identity.
- Stream world: switch + Go Live + Test + account zone right (Sign In until
  connected, then avatar with Change Account/Logout context menu).
- Test is a child of Stream: procs only stream-armed AND signed-in.
- Running: one reality line "dot word elapsed" (REC/LIVE/TEST; green/red/
  gold) + End; worlds + switch retire.
- Gear moved up from bottom bar, ~3 wordmark letters past the brand, single
  click opens Settings/Bug/Feature/About menu (TASK 40 Unit B shipped early).
- Fix folded in: BeginTestStream now arms OnAirPillOn explicitly (unarmed
  pump booted with zero encoder outputs -> "At least one output is required"
  forced-stop cascade from TASK 41's pipeline).
- VM: world/reality props + RaiseTopBarModes() wired into StreamStatus,
  pill, IsRecording, IsTestStream, IsConnected setters.

Doc: ai.md top-bar model, ViewModels/index.md, Controls/index.md, TASKS.md,
HANDOFF.md, new TASKS/task-42-top-bar-redesign.md; task-40 note.

Tests: TopBarModeTests.cs (new Good Dog), PillRadioTests + TestStreamTests
gates updated. Build 0 warnings; full suite 314/315 — single abort is the
pre-existing env-dependent RealMouseDrag test (Path of Exile 2 running)

TASKS.md

@@ -57,6 +57,7 @@
 | 39 | YPP journey tracker (slice 1: current-scope data) | 🔶 Slice 1 ✅ — 2026-09-22; slice 2 (Analytics + ETA) queued | [`TASKS/task-39-ypp-journey-tracker.md`](TASKS/task-39-ypp-journey-tracker.md) |
 | 40 | App Settings round: active-camera picker + config dialog, gear move, defaults, accent | ☐ Queued (2026-09-22) — plan saved | [`TASKS/task-40-app-settings-round.md`](TASKS/task-40-app-settings-round.md) |
 | 41 | Test Stream mode: private test broadcast + TEST drawer (mock chat input + simulated events) | ✅ Done (2026-09-22) | [`TASKS/task-41-test-stream-mode.md`](TASKS/task-41-test-stream-mode.md) |
+| 42 | Top bar redesign: one REC-or-Stream surface, gear up top, sign-in/account zone world-gated | ✅ Done (2026-09-22) | [`TASKS/task-42-top-bar-redesign.md`](TASKS/task-42-top-bar-redesign.md) |
 
 ---
 
@@ -84,7 +85,9 @@
   tweaks), **B** gear moved top-left right of the wordmark (left-click App Settings, right-click
   Bug/Feature/About), **C** persist output resolution default + surface default scene
   transition/duration + confirm-before-End, **D** accent/theme color (consolidate 69 hardcoded
-  accent sites into a DynamicResource brush + picker).
+  accent sites into a DynamicResource brush + picker). **Unit B (gear) is DONE early** — shipped 2026-09-22
+  as part of TASK 42 (top bar redesign): gear top-right of the brand, single click = the Settings/Bug/
+  Feature/About menu, removed from BottomBar. A + C + D remain queued.
 - **TASK 37** — queued (2026-09-20): split the layout data into a `default` set (the established DB)
   and a `current` set carrying the build-id; a saved `current` is honored only by the same build-id,
   otherwise defaults load — enables one-click revert to defaults too. Capture needed work OUT of