average_precision_score produces unexpected output when scoring a single sample

### Describe the bug

When using `average_precision_score` and scoring a single sample, the metric ignores `y_score` and will always produce a score of 1.0 if `y_true = [1]` and otherwise will return a score of 0. I would have expected that it would instead raise an exception.

Potentially related to #30147, however I'm focusing on the minimal example with just a single sample.

### Steps/Code to Reproduce

```python
from sklearn.metrics import average_precision_score

y_score = [0]
y_true = [1]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 1.0

y_score = [1]
y_true = [1]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 1.0

y_score = [0.5]
y_true = [1]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 1.0

y_score = [0]
y_true = [0]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 0.0

y_score = [1]
y_true = [0]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 0.0

y_score = [0.5]
y_true = [0]
score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 0.0
```

Additionally, you can see that the average_precision_score returns a score opposite of what precision and recall return:

```python
from sklearn.metrics import average_precision_score, precision_score, recall_score

y_score = [0]
y_true = [1]

score = average_precision_score(y_true=y_true, y_score=y_score)
print(score)  # 1.0
score = precision_score(y_true=y_true, y_pred=y_score)
print(score)  # 0.0
score = recall_score(y_true=y_true, y_pred=y_score)
print(score)  # 0.0
```

### Expected Results

I would have expected the metric to raise an exception, similar to what happens when ROC_AUC is called with a single sample:

```python
score = roc_auc_score(y_true=y_true, y_score=y_score)
print(score)

```

```
ValueError: Only one class present in y_true. ROC AUC score is not defined in that case.
```

### Actual Results

Refer to code snippets above.

### Versions

```shell
System:
    python: 3.11.10 | packaged by conda-forge | (main, Sep 30 2024, 18:08:57) [GCC 13.3.0]
executable: /opt/conda/envs/ag-311/bin/python
   machine: Linux-5.15.0-1056-aws-x86_64-with-glibc2.31

Python dependencies:
      sklearn: 1.5.1
          pip: 24.2
   setuptools: 60.2.0
        numpy: 1.26.4
        scipy: 1.12.0
       Cython: None
       pandas: 2.2.3
   matplotlib: 3.9.2
       joblib: 1.4.2
threadpoolctl: 3.5.0

Built with OpenMP: True

threadpoolctl info:
       user_api: blas
   internal_api: openblas
    num_threads: 128
         prefix: libopenblas
       filepath: /opt/conda/envs/ag-311/lib/libopenblasp-r0.3.28.so
        version: 0.3.28
threading_layer: pthreads
   architecture: SapphireRapids

       user_api: blas
   internal_api: openblas
    num_threads: 64
         prefix: libopenblas
       filepath: /opt/conda/envs/ag-311/lib/python3.11/site-packages/scipy.libs/libopenblasp-r0-23e5df77.3.21.dev.so
        version: 0.3.21.dev
threading_layer: pthreads
   architecture: Cooperlake

       user_api: openmp
   internal_api: openmp
    num_threads: 192
         prefix: libgomp
       filepath: /opt/conda/envs/ag-311/lib/python3.11/site-packages/scikit_learn.libs/libgomp-a34b3233.so.1.0.0
        version: None
```
```

COMMENT:
@Innixma @ogrisel

Labels: Bug, Needs Investigation