agregar ALTER TABLE migration en Rust para columnas nuevas en BD existentes

src-tauri/src/db.rs

@@ -315,6 +315,26 @@ async fn get_conn(db_path: &str) -> Result<libsql::Connection, String> {
     .await
     .map_err(|e| format!("Migration: {e}"))?;
 
+    // Migraciones post-CREATE: agregar columnas que pueden no existir en BD viejas
+    for alter in &[
+        "ALTER TABLE projects ADD COLUMN hus_count INTEGER DEFAULT 0",
+        "ALTER TABLE projects ADD COLUMN epics_count INTEGER DEFAULT 0",
+        "ALTER TABLE epics ADD COLUMN item_type TEXT DEFAULT 'E'",
+        "ALTER TABLE epics ADD COLUMN hierarchy_path TEXT",
+        "ALTER TABLE user_stories ADD COLUMN item_type TEXT DEFAULT 'U'",
+        "ALTER TABLE user_stories ADD COLUMN hierarchy_path TEXT",
+        "ALTER TABLE user_stories ADD COLUMN parent_code TEXT",
+        "ALTER TABLE work_items ADD COLUMN epic_id INTEGER",
+        "ALTER TABLE work_items ADD COLUMN parent_type TEXT",
+        "ALTER TABLE work_items ADD COLUMN parent_id INTEGER",
+        "ALTER TABLE work_items ADD COLUMN story_points REAL",
+        "ALTER TABLE work_items ADD COLUMN estimated_hours REAL",
+        "ALTER TABLE work_items ADD COLUMN actual_hours REAL",
+        "ALTER TABLE work_items ADD COLUMN assigned_to INTEGER",
+    ] {
+        let _ = conn.execute(alter, ()).await;
+    }
+
     // Copiar DB al Desktop para acceso rápido con DBeaver
     let _ = std::fs::copy(
         db_path,