Fix warnings

Author: staadecker

docs/learn/concepts/addition.md

@@ -213,6 +213,11 @@ Option 2 hardly seems reasonable this time considering that air emissions make u
 
 In practice, you'll find that it is common to want to keep extra labels on both sides of an addition or subtraction. As such, Pyoframe offers the bitwise OR operator (`|`) as a convenient shortcut. Instead of
 
+<!-- invisible-code-block: python
+a = model.air_emissions
+b = model.ground_emissions
+-->
+
 ```python
 a.keep_extras() + b.keep_extras()
 ```

docs/learn/migrate/v1.0.md

@@ -6,7 +6,7 @@ Pyoframe version 1.0 brings major improvements :tada:
 - **Bug fixes:** notably with `Variable(equals=…)` not properly parsing DataFrames.
 - **Improved performance** after rewriting internal functions based on extensive benchmarking.
 - **Smoother developer experience**, notably error messages explain the mathematical operations that led to an error and Pyoframe objects now print as legible tables.
-- **Improved documentation** including a revamped [API page](../../reference/index.md), an [examples page](../../examples/index.md), new explanations of functions like [`.over(…)`](../concepts/addition.md#adding-expressions-with-differing-dimensions-using-over), and the ability to view previous versions of the documentation.
+- **Improved documentation** including a revamped [API page](../../reference/index.md), an [examples page](../../examples/index.md), new explanations of functions like [`.over(…)`](../concepts/addition.md#over), and the ability to view previous versions of the documentation.
 - **More readable syntax** like our decision to rename `add_dim` to `over` and the changes to `.sum()` (see below).
 
 Unfortunately, these improvements involve some breaking changes. This page will guide you in migrating your code to v1.0.
@@ -78,7 +78,7 @@ Please update all uses of `pf.sum` and `pf.sum_by` accordingly.
 
 ### 3. Rename `.add_dim(…)` to `.over(…)`
 
-For clarity, `.add_dim(…)` was renamed to [`.over(…)`](../concepts/addition.md#adding-expressions-with-differing-dimensions-using-over). Please update your code accordingly.
+For clarity, `.add_dim(…)` was renamed to [`.over(…)`](../concepts/addition.md#over). Please update your code accordingly.
 
 ```python
 m.X.add_dim("time")  # before

src/pyoframe/_core.py

@@ -2240,7 +2240,7 @@ class Variable(BaseOperableBlock):
     """A decision variable for an optimization model.
 
     !!! tip
-        If `lb` or `ub` are a dimensioned object (e.g. an [Expression][pyoframe.Expression]), they will automatically be [broadcasted](../../learn/concepts/addition.md#adding-expressions-with-differing-dimensions-using-over) to match the variable's dimensions.
+        If `lb` or `ub` are a dimensioned object (e.g. an [Expression][pyoframe.Expression]), they will automatically be [broadcasted](../../learn/concepts/addition.md#over) to match the variable's dimensions.
 
     Parameters:
         *indexing_sets: