Fix pyright type errors across codebase

- Add pyrightconfig.json for pyright 1.1.408 TOML parsing workaround
- Add NoReturn annotations to fatal() functions for proper type narrowing
- Add None checks and assertions after require=True get_record() calls
- Fix AttrDict class with __getattr__ for dynamic attribute access
- Add type annotations and casts for Kubernetes client objects
- Store compose config as DockerDeployer instance attributes
- Filter None values from dotenv and environment mappings
- Use hasattr/getattr patterns for optional container attributes

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

stack_orchestrator/repos/fetch_stack.py

@@ -36,7 +36,9 @@ from stack_orchestrator.util import error_exit
 @click.pass_context
 def command(ctx, stack_locator, git_ssh, check_only, pull):
     """Optionally resolve then git clone a repository with stack definitions."""
-    dev_root_path = os.path.expanduser(config("CERC_REPO_BASE_DIR", default="~/cerc"))
+    dev_root_path = os.path.expanduser(
+        str(config("CERC_REPO_BASE_DIR", default="~/cerc"))
+    )
     if not opts.o.quiet:
         print(f"Dev Root is: {dev_root_path}")
     try: