Initial braindump app implementation

Create a complete braindump note-taking application with Dioxus 0.7 featuring:
- Note capture with title, content, and tags
- Full CRUD operations (create, read, update, delete)
- Search functionality for notes
- Tag-based filtering
- Note pinning for quick access
- Modern dark theme with purple accents
- Responsive sidebar layout
- Clean card-based note list
- Full-text editor with auto-save hint

Implemented with:
- Dioxus 0.7.1 fullstack for reactive UI and server functions
- Workspace pattern with shared API crate
- In-memory storage using LazyLock
- Server functions for note management

All core features working and ready for testing.

packages/ui/assets/styling/navbar.css

@@ -0,0 +1,16 @@
+#navbar {
+  display: flex;
+  flex-direction: row;
+}
+
+#navbar a {
+  color: #ffffff;
+  margin-right: 20px;
+  text-decoration: none;
+  transition: color 0.2s ease;
+}
+
+#navbar a:hover {
+  cursor: pointer;
+  color: #91a4d2;
+}