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/components/app_shell.rs

@@ -2,15 +2,18 @@ use dioxus::prelude::*;
 
 use crate::app::Route;
 use crate::components::sidebar::Sidebar;
+use crate::components::toast::{ToastContainer, Toasts};
 
 #[component]
 pub fn AppShell() -> Element {
+    use_context_provider(Toasts::new);
     rsx! {
         div { class: "app-shell",
             Sidebar {}
             main { class: "main-content",
                 Outlet::<Route> {}
             }
+            ToastContainer {}
         }
     }
 }