Enhance API and configuration for Telegram miniapp

- Added support for CORS origins and a new environment variable for miniapp access control.
- Implemented date validation for API requests to ensure correct date formats.
- Updated FastAPI app to allow access without Telegram initData for local development.
- Enhanced error handling and logging for better debugging.
- Added tests for API functionality and Telegram initData validation.
- Updated README with new environment variable details and testing instructions.
- Modified Docker and Git ignore files to include additional directories and files.

tests/__init__.py

@@ -0,0 +1 @@
+# Tests package.

tests/test_config.py

@@ -0,0 +1,37 @@
+"""Tests for config.is_admin and config.can_access_miniapp."""
+import pytest
+
+import config
+
+
+def test_is_admin_true_when_in_admin_list(monkeypatch):
+    monkeypatch.setattr(config, "ADMIN_USERNAMES", {"admin1", "admin2"})
+    assert config.is_admin("admin1") is True
+    assert config.is_admin("ADMIN1") is True
+    assert config.is_admin("admin2") is True
+
+
+def test_is_admin_false_when_not_in_list(monkeypatch):
+    monkeypatch.setattr(config, "ADMIN_USERNAMES", {"admin1"})
+    assert config.is_admin("other") is False
+    assert config.is_admin("") is False
+
+
+def test_can_access_miniapp_allowed_username(monkeypatch):
+    monkeypatch.setattr(config, "ALLOWED_USERNAMES", {"user1"})
+    monkeypatch.setattr(config, "ADMIN_USERNAMES", set())
+    assert config.can_access_miniapp("user1") is True
+    assert config.can_access_miniapp("USER1") is True
+
+
+def test_can_access_miniapp_admin_has_access(monkeypatch):
+    monkeypatch.setattr(config, "ALLOWED_USERNAMES", set())
+    monkeypatch.setattr(config, "ADMIN_USERNAMES", {"admin1"})
+    assert config.can_access_miniapp("admin1") is True
+
+
+def test_can_access_miniapp_denied(monkeypatch):
+    monkeypatch.setattr(config, "ALLOWED_USERNAMES", {"user1"})
+    monkeypatch.setattr(config, "ADMIN_USERNAMES", set())
+    assert config.can_access_miniapp("other") is False
+    assert config.can_access_miniapp("") is False