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/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "ui"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+dioxus = { workspace = true }
+api = { workspace = true }
+
+[features]
+server = ["api/server"]