refactor: rename loader/model packages to loaders/models

- Rename docforge.loader → docforge.loaders and docforge.model → docforge.models
- Update all imports, type stubs, CLI, tests, and documentation references
- Align MkDocs navigation and docforge.nav.yml with new package structure
- Adjust module docstrings and comments for consistency with pluralized naming

docforge/__init__.py

@@ -4,7 +4,7 @@
 `doc-forge` is a renderer-agnostic Python documentation compiler designed for
 speed, flexibility, and beautiful output. It decouples the introspection of
 your code from the rendering process, allowing you to generate documentation
-for various platforms (starting with MkDocs) from a single internal model.
+for various platforms (starting with MkDocs) from a single internal models.
 
 ## Installation
 
@@ -45,16 +45,16 @@ pip install doc-forge
 
 ## Project Structure
 
-- `docforge.loader`: Introspects source code using static analysis (`griffe`).
-- `docforge.model`: The internal representation of your project, modules, and objects.
-- `docforge.renderers`: Converters that turn the model into physical files.
+- `docforge.loaders`: Introspects source code using static analysis (`griffe`).
+- `docforge.models`: The internal representation of your project, modules, and objects.
+- `docforge.renderers`: Converters that turn the models into physical files.
 - `docforge.nav`: Managers for logical-to-physical path mapping and navigation.
 """
 
-from .loader import GriffeLoader, discover_module_paths
+from .loaders import GriffeLoader, discover_module_paths
 from .renderers import MkDocsRenderer
 from .cli import main
-from . import model
+from . import models
 
 __all__ = [
     "GriffeLoader",