feat(frontend): skeleton loading states, empty-state glow, light-mode polish

- Add shared skeleton building blocks (SkeletonHero, SkeletonMetricRow,
  SkeletonPanel, SkeletonRows) and wire them into every view's initial
  loading branch, replacing bare spinners for a cohesive shimmering shell.
- Polish EmptyState with a glow-ring icon chip instead of a flat icon.
- Harden .light theme: color-scheme, tuned scrollbar + selection for pale
  canvas. Dark/light theme toggle (next-themes) already persisted in TopBar.

services/frontend/src/app/(dashboard)/analysis/view.tsx

@@ -4,7 +4,7 @@ import { Hash, Search, Sparkles, TrendingUp } from "lucide-react";
 import { useEffect, useState } from "react";
 import { useAmbient } from "@/components/ambient/ambient-context";
 import { Avatar, Badge, GlassPanel, Input } from "@/components/primitives";
-import { EmptyState, LoadingState, SectionHeader } from "@/components/shared";
+import { EmptyState, SectionHeader, SkeletonRows } from "@/components/shared";
 import { useChannels, useMessageSearch, useTopReactors } from "@/hooks";
 import { aiTone } from "@/lib/ai-status";
 import {
@@ -70,7 +70,7 @@ export function AnalysisView() {
             }
           />
           {query.trim().length >= 2 && search.isLoading && (
-            <LoadingState label="Scanning" />
+            <SkeletonRows rows={6} />
           )}
           {(search.data ?? []).length === 0 ? (
             <EmptyState