Add DAST, graph modules, toast notifications, and dashboard enhancements

Add DAST scanning and code knowledge graph features across the stack:
- compliance-dast and compliance-graph workspace crates
- Agent API handlers and routes for DAST targets/scans and graph builds
- Core models and traits for DAST and graph domains
- Dashboard pages for DAST targets/findings/overview and graph explorer/impact
- Toast notification system with auto-dismiss for async action feedback
- Button click animations and disabled states for better UX

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

compliance-dashboard/src/app.rs

@@ -20,6 +20,20 @@ pub enum Route {
         SbomPage {},
         #[route("/issues")]
         IssuesPage {},
+        #[route("/graph")]
+        GraphIndexPage {},
+        #[route("/graph/:repo_id")]
+        GraphExplorerPage { repo_id: String },
+        #[route("/graph/:repo_id/impact/:finding_id")]
+        ImpactAnalysisPage { repo_id: String, finding_id: String },
+        #[route("/dast")]
+        DastOverviewPage {},
+        #[route("/dast/targets")]
+        DastTargetsPage {},
+        #[route("/dast/findings")]
+        DastFindingsPage {},
+        #[route("/dast/findings/:id")]
+        DastFindingDetailPage { id: String },
         #[route("/settings")]
         SettingsPage {},
 }