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README.md

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+# ToDo
+
+Small **C++/Qt** (Widgets) task list application with local **SQLite** persistence.
+
+## Features
+
+- Create, rename, and delete lists.
+- Create, edit, and delete notes/tasks.
+- Mark tasks as completed.
+- Automatic local save in a SQLite database.
+
+## Requirements
+
+- Qt (`widgets` and `sql` modules)
+- `qmake`
+- A C++17 compiler
+
+## Quick Build
+
+From the project root:
+
+```bash
+qmake ToDo.pro
+make
+```
+
+## Run the Application
+
+```bash
+./ToDo
+```
+
+## Data
+
+Data is stored in a `todo.sqlite3` SQLite file, created in the app data directory (`QStandardPaths::AppDataLocation`).
+
+## Project Structure
+
+- `src/gui`: user interface (windows, dialogs).
+- `src/core`: business services (`ListService`, `NoteService`).
+- `src/obj`: domain objects (`List`, `Note`).