Eliminate use of the include-markdown plugin for MkDocs

.github/CONTRIBUTING.md

@@ -93,20 +93,19 @@ for a list of dependencies needed for building `cmd2`.
 See the `dev` list under the `[dependency-groups]` heading in [pyproject.toml](../pyproject.toml)
 for a list of dependencies needed for building `cmd2`.
 
-| Prerequisite                                                                               | Minimum Version | Purpose                          |
-| ------------------------------------------------------------------------------------------ | --------------- | -------------------------------- |
-| [codecov](http://doc.pytest.org/en/latest/)                                                | `2.1.13`        | Cover coverage reporting         |
-| [invoke](https://www.pyinvoke.org/)                                                        | `2.2.0`         | Command automation               |
-| [mypy](https://mypy-lang.org/)                                                             | `1.13.0`        | Static type checker              |
-| [pytest](https://docs.pytest.org/en/stable/)                                               | `3.0.6`         | Unit and integration tests       |
-| [pytest-cov](http://doc.pytest.org/en/latest/)                                             | `6.0.0`         | Pytest code coverage             |
-| [pytest-mock](https://pypi.org/project/pytest-mock/)                                       | `3.14.0`        | Pytest mocker fixture            |
-| [mkdocs-include-markdown-plugin](https://pypi.org/project/mkdocs-include-markdown-plugin/) | `7.1.2`         | MkDocs Plugin include MkDn       |
-| [mkdocs-macros-plugin](https://mkdocs-macros-plugin.readthedocs.io/)                       | `1.3.7`         | MkDocs Plugin for macros         |
-| [mkdocs-material](https://squidfunk.github.io/mkdocs-material/)                            | `9.5.49`        | Documentation                    |
-| [mkdocstrings[python]](https://mkdocstrings.github.io/)                                    | `0.27.0`        | MkDocs Plugin for Python AutoDoc |
-| [ruff](https://github.com/astral-sh/ruff)                                                  | `0.7.3`         | Fast linter and formatter        |
-| [uv](https://github.com/astral-sh/uv)                                                      | `0.5.1`         | Python package management        |
+| Prerequisite                                                         | Minimum Version | Purpose                          |
+| -------------------------------------------------------------------- | --------------- | -------------------------------- |
+| [codecov](http://doc.pytest.org/en/latest/)                          | `2.1.13`        | Cover coverage reporting         |
+| [invoke](https://www.pyinvoke.org/)                                  | `2.2.0`         | Command automation               |
+| [mypy](https://mypy-lang.org/)                                       | `1.13.0`        | Static type checker              |
+| [pytest](https://docs.pytest.org/en/stable/)                         | `3.0.6`         | Unit and integration tests       |
+| [pytest-cov](http://doc.pytest.org/en/latest/)                       | `6.0.0`         | Pytest code coverage             |
+| [pytest-mock](https://pypi.org/project/pytest-mock/)                 | `3.14.0`        | Pytest mocker fixture            |
+| [mkdocs-macros-plugin](https://mkdocs-macros-plugin.readthedocs.io/) | `1.3.7`         | MkDocs Plugin for macros         |
+| [mkdocs-material](https://squidfunk.github.io/mkdocs-material/)      | `9.5.49`        | Documentation                    |
+| [mkdocstrings[python]](https://mkdocstrings.github.io/)              | `0.27.0`        | MkDocs Plugin for Python AutoDoc |
+| [ruff](https://github.com/astral-sh/ruff)                            | `0.7.3`         | Fast linter and formatter        |
+| [uv](https://github.com/astral-sh/uv)                                | `0.5.1`         | Python package management        |
 
 If Python is already installed in your machine, run the following commands to validate the versions:
 

docs/examples/examples.md

@@ -1,5 +1,3 @@
 # List of cmd2 examples
 
-{%
-   include-markdown "../../examples/README.md"
-%}
+--8<-- "docs/../examples/README.md"

docs/index.md

@@ -25,46 +25,39 @@ app = App()
 app.cmdloop()
 ```
 
-<!-- Getting Started -->
+## Getting Started
 
-{%
-   include-markdown "./overview/index.md"
-%}
+See the [Getting Started](overview/index.md) section for info on how to get started building a
+`cmd2` application.
 
-<!-- Migrating from cmd -->
+## Migrating from cmd2
 
-{%
-   include-markdown "./migrating/index.md"
-%}
+See the [Migrating from cmd2](migrating/index.md) section for info on how to migrate a `cmd`
+application to `cmd2`.
 
 ## Features
 
-{%
-   include-markdown "./features/index.md"
-    start="<!--intro-start-->"
-    end="<!--intro-end-->"
-%}
+See the [Features](features/index.md) section for a detailed guide to the features available within
+`cmd2`.
 
 ## Examples
 
-{%
-   include-markdown "./examples/index.md"
-    start="<!--intro-start-->"
-    end="<!--intro-end-->"
-%}
+See the [Examples](examples/index.md) section for various examples of using `cmd2`.
 
 ## Mixins
 
-{%
-   include-markdown "./mixins/index.md"
-    start="<!--intro-start-->"
-    end="<!--intro-end-->"
-%}
+See the [Mixins](mixins/index.md) section for info on how to extend `cmd2` using mixins.
 
-## [Testing](testing.md)
+## Testing
 
-## [API Reference](api/index.md)
+See the [Testing](testing.md) section for special considerations when writing unit or integration
+tests for a `cmd2` application.
+
+## API Reference
+
+See the [API Reference](api/index.md) for detailed information on the public API of `cmd2`.
 
 ## Meta
 
-[Documentation Conventions](doc_conventions.md)
+See the [Documentation Conventions](doc_conventions.md) for info on conventions used in this
+documentation.

mkdocs.yml

@@ -60,10 +60,6 @@ theme:
 plugins:
   - search
   - git-revision-date-localized
-  - include-markdown:
-      preserve_includer_indent: true
-      dedent: true
-      comments: false
   - macros:
       render_by_default: false
       on_error_fail: true
@@ -121,6 +117,9 @@ markdown_extensions:
   - pymdownx.inlinehilite
   - pymdownx.keys
   - pymdownx.smartsymbols
+  - pymdownx.snippets:
+      base_path: [".", "docs"]
+      check_paths: true
   - pymdownx.superfences:
       custom_fences:
         - name: mermaid
@@ -137,7 +136,7 @@ validation:
     absolute_links: info
   links:
     not_found: warn
-    absolute_links: info
+    absolute_links: ignore
     unrecognized_links: info
 
 not_in_nav: |

pyproject.toml

@@ -45,7 +45,6 @@ dev = [
     "invoke>=2.2.1",
     "ipython>=8.23",
     "mkdocs-git-revision-date-localized-plugin>=1.5",
-    "mkdocs-include-markdown-plugin>=7",
     "mkdocs-macros-plugin>=1.2",
     "mkdocs-material>=9.7.1",
     "mkdocstrings[python]>=1",
@@ -60,7 +59,6 @@ dev = [
 docs = [
     "black>=25",
     "mkdocs-git-revision-date-localized-plugin>=1.5",
-    "mkdocs-include-markdown-plugin>=7",
     "mkdocs-macros-plugin>=1.2",
     "mkdocs-material>=9.7.1",
     "mkdocstrings[python]>=1",