fix(packaging): stop including legacy pkgmgr.installers package

- Restrict setuptools package discovery to src/ (pkgmgr* only)
- Drop config/ as a Python package mapping (keep config as plain data dir)
- Remove config_defaults fallback paths and use config/ exclusively
- Add unit + integration tests for defaults.yaml loading and CLI update copying

https://chatgpt.com/share/6947e74f-573c-800f-b93d-5ed341fcd1a3

tests/integration/test_config_defaults_integration.py

@@ -0,0 +1,124 @@
+# tests/integration/test_config_defaults_integration.py
+from __future__ import annotations
+
+import os
+import sys
+import tempfile
+import types
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+import yaml
+
+from pkgmgr.core.config.load import load_config
+from pkgmgr.cli.commands import config as config_cmd
+
+
+class ConfigDefaultsIntegrationTest(unittest.TestCase):
+    def test_defaults_yaml_is_loaded_and_can_be_copied_to_user_config_dir(self):
+        """
+        Integration test:
+        - Create a temp "site-packages/pkgmgr" fake install root
+        - Put defaults under "<project_root>/config/defaults.yaml"
+          where project_root == pkg_root.parent (as per your current logic)
+        - Verify:
+            A) load_config() picks up defaults from that config folder when user dir has no defaults
+            B) _update_default_configs() copies defaults.yaml into ~/.config/pkgmgr/
+        """
+
+        with tempfile.TemporaryDirectory() as td:
+            root = Path(td)
+
+            # Fake HOME for user config
+            home = root / "home"
+            user_cfg_dir = home / ".config" / "pkgmgr"
+            user_cfg_dir.mkdir(parents=True)
+            user_config_path = str(user_cfg_dir / "config.yaml")
+
+            # Create a user config file that should NOT be overwritten by update
+            (user_cfg_dir / "config.yaml").write_text(
+                yaml.safe_dump({"directories": {"user_only": "/home/user"}}),
+                encoding="utf-8",
+            )
+
+            # Fake pkg install layout:
+            # pkg_root = <root>/site-packages/pkgmgr
+            # project_root = pkg_root.parent = <root>/site-packages
+            site_packages = root / "site-packages"
+            pkg_root = site_packages / "pkgmgr"
+            pkg_root.mkdir(parents=True)
+
+            # This is the "project_root/config" candidate for both:
+            # - load.py: roots include pkg_root.parent -> site-packages, so it checks site-packages/config
+            # - cli/config.py: project_root == pkg_root.parent -> site-packages, so it checks site-packages/config
+            config_dir = site_packages / "config"
+            config_dir.mkdir(parents=True)
+
+            defaults_payload = {
+                "directories": {
+                    "repositories": "/opt/Repositories",
+                    "binaries": "/usr/local/bin",
+                },
+                "repositories": [
+                    {"provider": "github", "account": "acme", "repository": "demo"}
+                ],
+            }
+            (config_dir / "defaults.yaml").write_text(
+                yaml.safe_dump(defaults_payload),
+                encoding="utf-8",
+            )
+
+            # Provide fake pkgmgr module so your functions resolve pkg_root correctly
+            fake_pkgmgr = types.SimpleNamespace(__file__=str(pkg_root / "__init__.py"))
+
+            with patch.dict(sys.modules, {"pkgmgr": fake_pkgmgr}):
+                with patch.dict(os.environ, {"HOME": str(home)}):
+                    # A) load_config should fall back to site-packages/config/defaults.yaml
+                    merged = load_config(user_config_path)
+
+                    self.assertEqual(
+                        merged["directories"]["repositories"], "/opt/Repositories"
+                    )
+                    self.assertEqual(
+                        merged["directories"]["binaries"], "/usr/local/bin"
+                    )
+
+                    # user-only key must still exist (user config merges over defaults)
+                    self.assertEqual(merged["directories"]["user_only"], "/home/user")
+
+                    self.assertIn("repositories", merged)
+                    self.assertTrue(
+                        any(
+                            r.get("provider") == "github"
+                            and r.get("account") == "acme"
+                            and r.get("repository") == "demo"
+                            for r in merged["repositories"]
+                        )
+                    )
+
+                    # B) update_default_configs should copy defaults.yaml to ~/.config/pkgmgr/
+                    # (and should not overwrite config.yaml)
+                    before_config_yaml = (user_cfg_dir / "config.yaml").read_text(
+                        encoding="utf-8"
+                    )
+
+                    config_cmd._update_default_configs(user_config_path)
+
+                    self.assertTrue((user_cfg_dir / "defaults.yaml").is_file())
+                    copied_defaults = yaml.safe_load(
+                        (user_cfg_dir / "defaults.yaml").read_text(encoding="utf-8")
+                    )
+                    self.assertEqual(
+                        copied_defaults["directories"]["repositories"],
+                        "/opt/Repositories",
+                    )
+
+                    after_config_yaml = (user_cfg_dir / "config.yaml").read_text(
+                        encoding="utf-8"
+                    )
+                    self.assertEqual(after_config_yaml, before_config_yaml)
+
+
+if __name__ == "__main__":
+    unittest.main()