chore: trim shipped size (right-size sidebar logo, strip symbols, unship dev harness)

- public/assets/icon.png was a 512px/225KB glossy render used for a 28px
  sidebar logo — downscale to 128px/16KB (saves ~209KB in the bundle).
- profile.release strip: debuginfo -> symbols (drops symbol names too;
  debuginfo was already stripped, backtraces already symbol-only).
- Move public/hotspot-test.html (a stale dev calibration page with broken
  .png asset refs) to dev/ so vite stops copying it into the release bundle.

Author: danscMax

public/hotspot-test.html dev/hotspot-test.htmlpublic/hotspot-test.html renamed to dev/hotspot-test.html

@@ -105,4 +105,4 @@ debug = "line-tables-only"
 [profile.release]
 lto = true
 codegen-units = 1
-strip = "debuginfo"
+strip = "symbols"

public/assets/icon.png

@@ -2,7 +2,7 @@ import type { ControlId } from "../config";
 import type { HotspotPosition } from "./types";
 
 /** Hotspot positions for the TOP-DOWN photo (naga-top.webp).
- *  Measured via hotspot-test.html click calibration. */
+ *  Measured via dev/hotspot-test.html click calibration (dev-only, not shipped). */
 export const topViewHotspots: Partial<Record<ControlId, HotspotPosition>> = {
   mouse_left:        { left: 25.5, top: 10, label: "control.name.mouseLeft" },
   wheel_up:          { left: 45.5, top: 13.5, label: "▲", size: "sm" },