[TRACKER] Controls Customization: Mobile Controls Visual Configuration in Creator Hub

## **⚠️ Problem:**
Mobile controls customization shipped in SDK7 and is documented, but configuring it means hand-writing `TouchScreenControls` — non-code creators can't reshape the HUD for their scene. Scenes ship mismatched default controls on mobile; adoption baseline unknown.

## **🏁 Scope:** [See docs](https://docs.decentraland.org/creator/scenes-sdk7/interactivity/touch-screen-controls)
Visual configuration of on-screen controls inside Creator Hub, covering every option the docs page allows: joystick + crosshair toggles, main action selector, per-button hide + icon override. Writes `TouchScreenControls` on the root entity. Out: `UiInputBinding` custom-UI authoring, new protocol fields.

## **📝 Deliverables:**
- [ ] Creator configures on-screen controls in Hub without writing code
- [ ] Every documented option exposed — joystick, crosshair, main action, per-button hide + icon
- [ ] Hand-written `TouchScreenControls` opens in the editor and round-trips unchanged
- [ ] Usage tracked in Hub analytics

## **🔗 References:**
- [On-screen Controls — SDK7 docs](https://docs.decentraland.org/creator/scenes-sdk7/interactivity/touch-screen-controls) — source of truth for the fields to expose: `hideJoystick`, `hideCrosshair`, `mainAction`, `touchInputs[].hide` / `.icon`, button priority stack, >5-button overflow
- [decentraland/docs#122](https://github.com/decentraland/docs/pull/122) — merged 2026-08-13; unblocks this issue, docs no longer pending
- [#2701](https://github.com/decentraland/godot-explorer/issues/2701) — launch comms for the SDK feature this editor wraps
- [#2348](https://github.com/decentraland/godot-explorer/issues/2348) — Adaptive Controls implementation; client-side defaults the editor overrides
- No prior art in creator-hub (searched `mobile controls`, `touch screen controls` in:title, 2026-08-26)

## **Notes**
- Surface: smart item in catalog vs inspector panel on root entity?
- Implementation repo — `decentraland/creator-hub`, tracked here?
- Figma for the panel missing.