Refactor project structure and enhance Docker configuration

- Updated `.dockerignore` to exclude test and development artifacts, optimizing the Docker image size.
- Refactored `main.py` to delegate execution to `duty_teller.run.main()`, simplifying the entry point.
- Introduced a new `duty_teller` package to encapsulate core functionality, improving modularity and organization.
- Enhanced `pyproject.toml` to define a script for running the application, streamlining the execution process.
- Updated README documentation to reflect changes in project structure and usage instructions.
- Improved Alembic environment configuration to utilize the new package structure for database migrations.

README.md

@@ -53,6 +53,12 @@ A minimal Telegram bot boilerplate using [python-telegram-bot](https://github.co
 python main.py
 ```
 
+Or after `pip install -e .`:
+
+```bash
+duty-teller
+```
+
 The bot runs in polling mode. Send `/start` or `/help` to your bot in Telegram to test.
 
 ## Run with Docker
@@ -75,18 +81,21 @@ Ensure `.env` exists (e.g. `cp .env.example .env`) and contains `BOT_TOKEN`.
 
 ## Project layout
 
-- `main.py` – Builds the `Application`, registers handlers, runs polling and FastAPI in a thread.
-- `config.py` – Loads `BOT_TOKEN`, `DATABASE_URL`, `ALLOWED_USERNAMES`, `ADMIN_USERNAMES`, `CORS_ORIGINS`, etc. from env; exits if `BOT_TOKEN` is missing. Optional `Settings` dataclass for tests.
-- `api/` – FastAPI app (`/api/duties`, `/api/calendar-events`), auth/session Depends, static webapp mount.
-- `db/` – SQLAlchemy models, session (use `session_scope` for all DB access), repository, schemas. One `DATABASE_URL` per process; set env before first import if you need a different URL in tests.
-- `handlers/` – Telegram command and chat handlers; thin layer that call services and utils.
-- `services/` – Business logic (group duty pin, import); accept session from caller.
-- `utils/` – Shared date, user, and handover helpers.
-- `alembic/` – Migrations (use `config.DATABASE_URL`).
+- `main.py` – Entry point: builds the `Application`, registers handlers, runs polling and FastAPI in a thread. Calls `duty_teller.config.require_bot_token()` so the app exits with a clear message if `BOT_TOKEN` is missing.
+- `duty_teller/` – Main package (install with `pip install -e .`). Contains:
+  - `config.py` – Loads `BOT_TOKEN`, `DATABASE_URL`, `ALLOWED_USERNAMES`, etc. from env; no exit on import; use `require_bot_token()` in `main` when running the bot. Optional `Settings` dataclass for tests. `PROJECT_ROOT` for webapp path.
+  - `api/` – FastAPI app (`/api/duties`, `/api/calendar-events`), `dependencies.py` (DB session, auth, date validation), static webapp mounted from `PROJECT_ROOT/webapp`.
+  - `db/` – SQLAlchemy models, session (`session_scope`), repository, schemas.
+  - `handlers/` – Telegram command and chat handlers; register via `register_handlers(app)`.
+  - `services/` – Business logic (group duty pin, import); accept session from caller.
+  - `utils/` – Shared date, user, and handover helpers.
+  - `importers/` – Duty-schedule JSON parser.
+- `alembic/` – Migrations (use `duty_teller.config.DATABASE_URL` and `duty_teller.db.models.Base`).
 - `webapp/` – Miniapp UI (calendar, duty list); served at `/app`.
-- `pyproject.toml` – Installable package (`pip install -e .`); `requirements.txt` – pinned deps.
+- `tests/` – Tests; `helpers.py` provides `make_init_data` for auth tests.
+- `pyproject.toml` – Installable package (`pip install -e .`).
 
-To add commands, define async handlers in `handlers/commands.py` (or a new module) and register them in `handlers/__init__.py`.
+To add commands, define async handlers in `duty_teller/handlers/commands.py` (or a new module) and register them in `duty_teller/handlers/__init__.py`.
 
 ## Импорт расписания дежурств (duty-schedule)