MIL-001: project foundation

pyproject.toml (Python >=3.13, no runtime dependencies, speech and dev extras),
Python .gitignore, layer skeleton with constants.py, Doxyfile, README with the
.venv instructions, the Malay to Danish word list and review record RC-023.

Task: MIL-001#1
Task: MIL-001#2
Task: MIL-001#3
Task: MIL-001#4
Task: MIL-001#5
Task: MIL-001#6

tests/unit/test_app.py

@@ -0,0 +1,11 @@
+"""Tests of the entry point.
+
+@file test_app.py
+@brief Checks main of flash_card.presentation.app.
+"""
+
+from flash_card.presentation.app import main
+
+
+def test_main_returns_zero_without_arguments() -> None:
+    assert main([]) == 0