fix: align Hyprland overlay windows to mpv and stop pinning them

- Force-apply exact Hyprland move/resize/setprop dispatches when bounds are provided
- Stop pinning overlay windows; toggle pin off when Hyprland reports pinned=true
- Compensate stats overlay outer placement for Electron/Wayland content insets
- Make stats overlay window and page opaque so mpv cannot show through transparent insets
- Constrain stats app to h-screen with internal scroll so content covers mpv from y=0
- Lock overlay/stats window titles against page-title-updated events
- Add regression coverage for placement dispatches, inset compensation, and CSS overlay mode

stats/src/styles/globals.css

@@ -34,17 +34,30 @@
   --font-mono: 'Geist Mono Variable', 'JetBrains Mono', 'Fira Code', ui-monospace, monospace;
 }
 
+html,
+body,
+#root {
+  width: 100%;
+  height: 100%;
+  min-height: 100%;
+}
+
 body {
   margin: 0;
   font-family: var(--font-sans);
   background-color: var(--color-ctp-base);
   color: var(--color-ctp-text);
+  overflow: hidden;
   -webkit-font-smoothing: antialiased;
   -moz-osx-font-smoothing: grayscale;
 }
 
 body.overlay-mode {
-  background-color: rgba(36, 39, 58, 0.85);
+  background-color: var(--color-ctp-base);
+}
+
+body.overlay-mode #root {
+  background-color: var(--color-ctp-base);
 }
 
 /* Custom scrollbar */

stats/src/styles/globals.test.ts

@@ -0,0 +1,15 @@
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import { fileURLToPath } from 'node:url';
+
+const css = readFileSync(fileURLToPath(new URL('./globals.css', import.meta.url)), 'utf8');
+
+test('stats overlay mode paints an opaque full-viewport background', () => {
+  assert.match(css, /html,\s*body,\s*#root\s*\{[^}]*height:\s*100%;/s);
+  assert.match(css, /body\.overlay-mode\s*\{[^}]*background-color:\s*var\(--color-ctp-base\);/s);
+  assert.doesNotMatch(css, /body\.overlay-mode\s*\{[^}]*rgba\(/s);
+  assert.match(
+    css,
+    /body\.overlay-mode #root\s*\{[^}]*background-color:\s*var\(--color-ctp-base\);/s,
+  );
+});