Fix load_yaml returning unresolved IncludeFile for top-level !include

Move the IncludeFile resolution into _load_yaml_internal so all callers
get resolved content, rather than patching individual call sites.

script/analyze_component_buses.py

@@ -221,9 +221,6 @@ def analyze_yaml_file(yaml_file: Path) -> dict[str, Any]:
 
     try:
         data = yaml_util.load_yaml(yaml_file)
-        # Top-level !include returns an IncludeFile that must be resolved
-        if isinstance(data, yaml_util.IncludeFile):
-            data = data.load()
         result["loaded"] = True
     except Exception:  # pylint: disable=broad-exception-caught
         return result

script/merge_component_configs.py

@@ -27,7 +27,6 @@ sys.path.insert(0, str(Path(__file__).parent.parent))
 
 from esphome import yaml_util
 from esphome.config_helpers import merge_config
-from esphome.yaml_util import IncludeFile
 from script.analyze_component_buses import PACKAGE_DEPENDENCIES, get_common_bus_packages
 
 # Prefix for dependency markers in package tracking
@@ -47,12 +46,7 @@ def load_yaml_file(yaml_file: Path) -> dict:
     if not yaml_file.exists():
         raise FileNotFoundError(f"YAML file not found: {yaml_file}")
 
-    data = yaml_util.load_yaml(yaml_file)
-    # Top-level !include (e.g., `!include common.yaml`) returns an IncludeFile
-    # that must be resolved before we can work with it as a dict.
-    if isinstance(data, IncludeFile):
-        data = data.load()
-    return data
+    return yaml_util.load_yaml(yaml_file)
 
 
 @lru_cache(maxsize=256)