Add App core struct with event-handling and initialization logic for TUI.

Cargo.toml

@@ -0,0 +1,51 @@
+[workspace]
+resolver = "2"
+members = [
+    "crates/owlen-core",
+    "crates/owlen-tui",
+    "crates/owlen-cli",
+    "crates/owlen-ollama",
+]
+exclude = []
+
+[workspace.dependencies]
+# Async runtime and utilities
+tokio = { version = "1.0", features = ["full"] }
+tokio-stream = "0.1"
+tokio-util = { version = "0.7", features = ["rt"] }
+futures = "0.3"
+futures-util = "0.3"
+
+# TUI framework
+ratatui = "0.28"
+crossterm = "0.28"
+
+# HTTP client and JSON handling
+reqwest = { version = "0.12", features = ["json", "stream"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
+
+# Utilities
+uuid = { version = "1.0", features = ["v4", "serde"] }
+anyhow = "1.0"
+thiserror = "1.0"
+
+# Configuration
+toml = "0.8"
+shellexpand = "3.1"
+
+# Database
+sled = "0.34"
+
+# For better text handling
+textwrap = "0.16"
+
+# Async traits
+async-trait = "0.1"
+
+# CLI framework
+clap = { version = "4.0", features = ["derive"] }
+
+# Dev dependencies
+tempfile = "3.8"
+tokio-test = "0.4"