fix(web): task launcher textarea no longer grows while typing; less transparent windows on Firefox

The launcher's textarea inherited the base Textarea component's default
field-sizing:content (auto-grow to fit typed content) — ChatThread's
input already overrides this with field-sizing-fixed, but the desktop
launcher never did, so the box would jump taller the moment you started
typing. Also bumps the floating-window frosted-glass opacity from 70%
to 85%: backdrop-filter's blur strength isn't consistent across
engines, and Firefox blurs noticeably less than Chromium at the same
radius, making the Chromium-tuned opacity look far too see-through
there.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/app.css

@@ -254,10 +254,15 @@
   flex-direction: column;
   box-sizing: border-box;
   pointer-events: auto;
-  /* Frosted glass — same recipe as the desktop's "What should Nomos do?"
-     launcher card (bg-card/70 backdrop-blur), so floating windows read as
-     part of the same surface language instead of opaque panels. */
-  background: color-mix(in oklab, var(--card) 70%, transparent);
+  /* Frosted glass — same idea as the desktop's "What should Nomos do?"
+     launcher card (bg-card/70 backdrop-blur), tuned less transparent
+     (85%, not 70%) because backdrop-filter's blur strength isn't
+     consistent across engines — Firefox blurs noticeably less than
+     Chromium at the same radius, so a Chromium-tuned opacity reads as
+     "way too see-through" there (2026-07-21). Leaning on a higher base
+     opacity keeps windows legible everywhere; the blur is a bonus on
+     top, not what's carrying the effect. */
+  background: color-mix(in oklab, var(--card) 85%, transparent);
   backdrop-filter: blur(8px);
   -webkit-backdrop-filter: blur(8px);
   color: var(--card-foreground);

web/src/lib/components/desktop-shell/TaskLauncher.svelte

@@ -50,7 +50,7 @@
       onkeydown={handleKeydown}
       placeholder="e.g. Roll the staging database back to last night's snapshot and verify the app is healthy…"
       rows={compact ? 2 : 3}
-      class="max-h-52 min-h-24 resize-none border-0 bg-transparent px-4 py-3.5 text-base shadow-none focus-visible:ring-0"
+      class="max-h-52 min-h-24 resize-none field-sizing-fixed border-0 bg-transparent px-4 py-3.5 text-base shadow-none focus-visible:ring-0"
     />
     <div class="flex items-center justify-between px-3 pb-3">
       <span class="text-[11px] text-muted-foreground">Enter to start · Shift+Enter for newline</span>