Could we please get wheels for Python 3.15?

### Describe the bug

Python 3.15rc1 came out this week. Testing other packages that happen to depend on aiohttp with 3.15rc1 (which is important -- the Python core devs specifically request testing with this release) currently requires building aiohttp from source, which is a pain.

### To Reproduce

Take for example github.com/microsoft/typeagent-py/. We're trying to prove that this builds with Python 3.15 but find that at least 5 packages need to be built from source; aiohttp is one of them.

```sh
uv run --python=3.15 python --version
```

shows that aiohttp is being built from source (at least the first time). (You also need to install rustc to build some other packages from scratch, notably tiktoken and pydantic-core.)

### Expected behavior

It should download a wheel for 3.15.0

### Logs/tracebacks

```python-traceback
None
```

### Python Version

```console
$ python --version
3.15.0rc1
```

### aiohttp Version

```console
$ python -m pip show aiohttp
Name: aiohttp
Version: 3.14.3
Location: /Users/guido/typeagent-py/.venv/lib/python3.15/site-packages
Requires: aiohappyeyeballs, aiosignal, attrs, frozenlist, multidict, propcache, yarl
```

### multidict Version

```console
$ python -m pip show multidict
Name: multidict
Version: 6.7.1
Location: /Users/guido/typeagent-py/.venv/lib/python3.15/site-packages
Requires:
Required-by: aiohttp, yarl
```

### propcache Version

```console
$ python -m pip show propcache
Name: propcache
Version: 0.5.2
Location: /Users/guido/typeagent-py/.venv/lib/python3.15/site-packages
Requires:
Required-by: aiohttp, yarl
```

### yarl Version

```console
$ python -m pip show yarl
Name: yarl
Version: 1.24.5
Location: /Users/guido/typeagent-py/.venv/lib/python3.15/site-packages
Requires: idna, multidict, propcache
Required-by: aiohttp
```

### OS

macOS 26.5.2

### Related component

Server

### Additional context

None

### Code of Conduct

- [x] I agree to follow the aio-libs Code of Conduct