fix: creator feedback batch Branch 1 — TRAX volume, tooltip, meter boost, slider click, backdrop

- TRAX: LocalGain now applies 0.2× factor so music is quieter relative to desktop audio slider
- TRAX tooltip: switched to ToolTipService with Placement=Top to fix z-order in Viewbox overlay
- Mic meter: MeterLevel multiplied by 1.2× before clamping for ~20% higher visual readout
- Volume sliders: click anywhere on track to jump thumb to that position before dragging
- Backdrop: Image Visibility now binds to BackdropVisible; compositor checks IsVisible before blit
- Renamed 'Backdrop' to 'Game Capture' in EnsureBackdrop + test assertions

TASKS.md

@@ -809,6 +809,21 @@ No changes to `MusicPlayer`, the 0.20 cap, the ducker, or the meter zones. Build
 
 ---
 
+## TASK 14 — Creator feedback batch: quick fixes (TRAX, meter, backdrop, sliders)
+
+**Goal:** address creator's immediate UX feedback from testing session.
+
+### Status: 🔶 In progress — Branch 1 (items 1–5) shipped
+
+1. ✅ TRAX volume — `LocalGain = GameAudioVolume * 0.2` so TRAX is 20% of the desktop audio slider (was 100%, now quieter)
+2. ✅ TRAX tooltip — replaced `ToolTip` binding with `ToolTipService.ToolTip` + `Placement="Top"` to fix z-order inside Viewbox overlay
+3. ✅ Mic meter boost — `MeterLevel` multiplied by 1.2× before clamping so the bar reads ~20% higher at same input level
+4. ✅ Click-to-position sliders — clicking anywhere on the mic/game volume slider track now jumps the thumb to that position before starting the drag
+5. ✅ Backdrop visibility — the dedicated `<Image>` now binds `Visibility` to `BackdropVisible` (ViewModel property); compositor checks `IsVisible` before blit
+6. ✅ Rename "Backdrop" → "Game Capture" in `EnsureBackdrop()` + test assertions
+
+---
+
 ## Backlog (future versions)
 
 1. v0.2 — Recording to local file (recordings carry the branding flash — see TASK 3 / `ai.md` Monetization)