feat(web): Identities + Campaigns list pages + THREAT DATA nav group

Adds proper /identities and /campaigns list pages following the
Bounty/Attackers convention (page-header + page-title-group +
controls-row + logs-section + logs-table + EmptyState). Both pages
live-update via the existing identity / campaign SSE streams.

Sidebar: Attackers, Identities, Campaigns now group under a
THREAT DATA NavGroup, matching the SWARM grouping pattern.

CampaignDetail and IdentityDetail rewritten to use the house class
system (page-header / logs-section / chip / dim-chip) instead of
inline styles. The campaign chip on IdentityDetail navigates to
/campaigns/:uuid; both pages share a small fp-group helper for
fingerprint listings (added to Dashboard.css).

decnet_web/src/App.tsx

@@ -19,7 +19,9 @@ const LiveLogs       = lazy(() => import('./components/LiveLogs'));
 const Webhooks       = lazy(() => import('./components/Webhooks'));
 const Attackers      = lazy(() => import('./components/Attackers'));
 const AttackerDetail = lazy(() => import('./components/AttackerDetail'));
+const Identities    = lazy(() => import('./components/Identities'));
 const IdentityDetail = lazy(() => import('./components/IdentityDetail'));
+const Campaigns     = lazy(() => import('./components/Campaigns'));
 const CampaignDetail = lazy(() => import('./components/CampaignDetail'));
 const Config         = lazy(() => import('./components/Config'));
 const Bounty         = lazy(() => import('./components/Bounty'));
@@ -115,7 +117,9 @@ const AuthedShell: React.FC<AuthedShellProps> = ({ onLogout, onSearch, searchQue
             <Route path="/credentials" element={<Credentials />} />
             <Route path="/attackers" element={<Attackers />} />
             <Route path="/attackers/:id" element={<AttackerDetail />} />
+            <Route path="/identities" element={<Identities />} />
             <Route path="/identities/:id" element={<IdentityDetail />} />
+            <Route path="/campaigns" element={<Campaigns />} />
             <Route path="/campaigns/:id" element={<CampaignDetail />} />
             <Route path="/config" element={<Config />} />
             <Route path="/swarm-updates" element={<RemoteUpdates />} />