Breaking changes in 0.10.0: async client configuration

## Breaking changes in `0.10.0` release

Starting with version `0.10.0`, the `aws-sdk-*` client packages include breaking changes to client configuration.

### New configuration object

The synchronous `Config` class previously exported from each service package has been replaced with a service-specific asynchronous configuration class.

For example, for Bedrock Runtime:

```python
# Before
from aws_sdk_bedrock_runtime.config import Config
```

is now:

```python
# 0.10.0 and later
from aws_sdk_bedrock_runtime.config import AsyncBedrockRuntimeConfig
```

### Configuration is now asynchronous

Configuration objects must now be created using the asynchronous `resolve()` method. Directly instantiating the configuration class is not supported and results in an error.

```python
# Incorrect
config = AsyncBedrockRuntimeConfig(
region="us-west-2",
)

# Raises
smithy_aws_core.config.exceptions.ConfigError: AsyncBedrockRuntimeConfig cannot be constructed directly. Use `await AsyncBedrockRuntimeConfig.resolve(...)` instead.
```

Instead, resolve the configuration before passing it to the client:

```python
from aws_sdk_bedrock_runtime.config import AsyncBedrockRuntimeConfig

config = await AsyncBedrockRuntimeConfig.resolve(
region="us-west-2",
)
```

This change allows the SDK to perform configuration resolution that requires I/O, such as reading shared AWS configuration and credentials files, without blocking the event loop.

Configuration values are resolved from explicit overrides passed to `resolve()`, environment variables, and shared AWS configuration and credentials files. If no configuration is provided when constructing a client, the SDK automatically resolves one for you.

### Plugins

Configuration plugins must now receive the service-specific asynchronous configuration type, `AsyncConfig`, instead of the previous `Config` type.

For example:

```python
# Before
from aws_sdk_bedrock_runtime.config import Config

def my_plugin(config: Config) -> None:
...
```

is now:

```python
# 0.10.0 and later
from aws_sdk_bedrock_runtime.config import AsyncBedrockRuntimeConfig

def my_plugin(config: AsyncBedrockRuntimeConfig) -> None:
...
```

### Migrating existing applications

Update configuration usage as follows:

1. Replace imports of `Config` with the service-specific `AsyncConfig`.
2. Replace direct configuration construction with `await AsyncConfig.resolve(...)`.
3. Ensure explicit configuration resolution occurs within an asynchronous context.
4. Update configuration plugins to accept the service-specific `AsyncConfig` type instead of `Config`.

For example:

```python
# Before
from aws_sdk_bedrock_runtime.client import AsyncBedrockRuntimeClient
from aws_sdk_bedrock_runtime.config import Config

def my_plugin(config: Config) -> None:
...

config = Config(
region="us-west-2",
)

client = AsyncBedrockRuntimeClient(
config=config,
plugins=[my_plugin],
)
```

becomes:

```python
# 0.10.0 and later
from aws_sdk_bedrock_runtime.client import AsyncBedrockRuntimeClient
from aws_sdk_bedrock_runtime.config import AsyncBedrockRuntimeConfig

def my_plugin(config: AsyncBedrockRuntimeConfig) -> None:
...

config = await AsyncBedrockRuntimeConfig.resolve(
region="us-west-2",
)

client = AsyncBedrockRuntimeClient(
config=config,
plugins=[my_plugin],
)
```

### Installing the latest version

Upgrade an existing client package with `pip`:

```bash
python -m pip install --upgrade aws-sdk-
```

For example:

```bash
python -m pip install --upgrade aws-sdk-bedrock-runtime
```

To explicitly require version `0.10.0` or later:

```bash
python -m pip install "aws-sdk-bedrock-runtime>=0.10.0"
```

### Pinning versions

To avoid unexpected breaking changes when installing or deploying your application, we recommend pinning `aws-sdk-*` client packages to a specific version or compatible version range.

To pin to an exact version:

```bash
python -m pip install "aws-sdk-bedrock-runtime==0.10.0"
```

To allow compatible patch releases while avoiding newer minor releases:

```bash
python -m pip install "aws-sdk-bedrock-runtime~=0.10.0"
```

This is important while the SDK is pre-`1.0.0`, when minor releases may include breaking changes.

Aucun fichier du dépôt ni aucun test n’est indiqué. Commencez par vérifier où sont maintenues les notes de version ou la documentation de migration pour la version 0.10.0, puis comparez avec l’issue les imports documentés de AsyncConfig, l’utilisation de resolve(), les types de plugin et les exemples de verrouillage des versions ; la tâche est terminée lorsque les indications concernant les breaking changes sont publiées à l’emplacement de documentation établi du projet.

Rédigé par le modèle d'indexation à partir du texte de l'issue.