docs: Sphinx documentation fixes

Broken links, invalid chapter underlining, invalid code fragments, etc.

docs/use_cases/custom_representation_types.rst

@@ -305,4 +305,4 @@ representation types with::
 
     For more examples of custom representation types usage please refer to the
     :ref:`use_cases/linear_algebra:Linear Algebra vs. Quantities` chapter and the
-    :ref:`examples/measurement:measurement` example.
+    :ref:`examples/custom_representation/measurement:measurement` example.

docs/use_cases/linear_algebra.rst

@@ -85,4 +85,4 @@ output:
 .. seealso::
 
     For more examples of Linear Algebra definition and operations please refer to
-    the :ref:`examples/linear_algebra:linear_algebra` example.
+    the :ref:`examples/custom_representation/linear_algebra:linear_algebra` example.

docs/use_cases/unknown_dimensions.rst

@@ -87,7 +87,7 @@ following::
 .. seealso::
 
     Another good example of unknown dimension usage can be found in the
-    :ref:`examples/box_example:box_example`::
+    :ref:`examples/basics/box_example:box_example`::
 
         std::cout << "float rise rate = " << box.fill_level(measured_mass) / fill_time << '\n';