i think i got step one working

src-tauri/src/lib.rs

@@ -1,16 +1,66 @@
+use tauri::Manager;
+
+// --- Commands ---
+
+/// Returns the backend URL. Stubbed for now; will be replaced once the
+/// Python/Rust backend is fully wired up.
+#[tauri::command]
+fn get_backend_url() -> String {
+    // During development the Python backend still runs on 8642.
+    // In production this will be replaced with a local Rust server or IPC.
+    "http://localhost:8642".to_string()
+}
+
+/// Minimal encrypt: base64-encodes the string as a placeholder until a proper
+/// OS keychain implementation is added (e.g. tauri-plugin-stronghold).
+#[tauri::command]
+fn encrypt_string(data: String) -> String {
+    use std::io::Write;
+    let encoded = data
+        .as_bytes()
+        .iter()
+        .fold(String::new(), |mut acc, b| {
+            use std::fmt::Write as FmtWrite;
+            let _ = write!(acc, "{:02x}", b);
+            acc
+        });
+    encoded
+}
+
+/// Companion decode for encrypt_string.
+#[tauri::command]
+fn decrypt_string(encrypted: String) -> Result<String, String> {
+    let bytes: Result<Vec<u8>, _> = (0..encrypted.len())
+        .step_by(2)
+        .map(|i| u8::from_str_radix(&encrypted[i..i + 2], 16))
+        .collect();
+    bytes
+        .map_err(|e| format!("decrypt error: {e}"))
+        .and_then(|b| String::from_utf8(b).map_err(|e| format!("utf8 error: {e}")))
+}
+
+// --- App entry point ---
+
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
-  tauri::Builder::default()
-    .setup(|app| {
-      if cfg!(debug_assertions) {
-        app.handle().plugin(
-          tauri_plugin_log::Builder::default()
-            .level(log::LevelFilter::Info)
-            .build(),
-        )?;
-      }
-      Ok(())
-    })
-    .run(tauri::generate_context!())
-    .expect("error while running tauri application");
+    tauri::Builder::default()
+        .plugin(tauri_plugin_dialog::init())
+        .plugin(tauri_plugin_fs::init())
+        .setup(|app| {
+            if cfg!(debug_assertions) {
+                app.handle().plugin(
+                    tauri_plugin_log::Builder::default()
+                        .level(log::LevelFilter::Info)
+                        .build(),
+                )?;
+            }
+            Ok(())
+        })
+        .invoke_handler(tauri::generate_handler![
+            get_backend_url,
+            encrypt_string,
+            decrypt_string,
+        ])
+        .run(tauri::generate_context!())
+        .expect("error while running tauri application");
 }