feat: implement DCOS source tree, tests, and build configuration

Complete implementation of the DCOS package including:
- 40+ Python source files across agents, communication, core, learning, memory, protocols, utils
- pyproject.toml build configuration
- 102 unit tests across all subsystems
- Fixed flake.nix (Python 3.12, proper dependencies, pyproject build)
- Fixed .woodpecker.yml (correct paths, removed silent-fail flags)
- Added .gitignore
- Cleared stale pytest cache

tests/test_utils/test_cli.py

@@ -0,0 +1,26 @@
+"""
+Tests for CLI module.
+"""
+
+import pytest
+from dcos.utils.cli import main
+
+
+class TestCLI:
+    def test_version(self):
+        result = main(["--version"])
+        assert result == 0
+
+    def test_status(self):
+        result = main(["status"])
+        assert result == 0
+
+    def test_info(self):
+        result = main(["info"])
+        assert result == 0
+
+    def test_unknown_command(self):
+        with pytest.raises(SystemExit) as exc:
+            main(["badcommand"])
+        # argparse exits with code 2 for invalid choices
+        assert exc.value.code == 2