## 🚀 Feature Proposal

#7753 added basic support for WebAuthn automation in the form of the `addVirtualAuthenticator` and `removeVirtualAuthenticator` methods. Implement the rest of the methods: `addCredential`, `getCredential`, `removeCredential`, `removeAllCredentials`, `setUserVerified`.

## Motivation

Support more WebAuthn use-cases, like logging in with a specific credential, handling user verification failures, and inspecting generated credentials.

## Example

For a page like this

```html
<button id="login">Log in with WebAuthn</button>
<span id="result"></span>
```

```javascript
document.getElmentById("login").addEventListener("click", () => {
  navigator.credentials.get({...}).then(assertion => {
    document.getElementById("result").innerText = "Success!";
  })
});
```

A test could be written like so:

```java
// Set up the virtual authenticator.
HasVirtualAuthenticator virtualAuthenticatorManager = ((HasVirtualAuthenticator) driver);
VirtualAuthenticatorOptions options = new VirtualAuthenticatorOptions();
VirtualAuthenticator authenticator =
    virtualAuthenticatorManager.addVirtualAuthenticator(options);

// New code: inject a credential into the authenticator.
// Without this API the developer would have to generate a credential through
// navigator.credentials.create({...}) on the javascript side and would have less
// control over the resulting PK.
Credential credential = Credential.createNonResidentCredential(...params);
virtualAuthenticatorManager.addCredential(authenticator, credential);

// Assert login successful:
driver.findElement(By.id("login")).click();
WebElement result = driver.findElement(By.id("result"));
new WebDriverWait(driver, 60, 1000).until(
    driver -> !result.getText().equals(""));
assertThat(result.getText()).isEqualTo("Success!");
```
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Collectors;
import java.util.stream.Stream;
@Augmentable
public class RemoteWebDriver implements WebDriver, JavascriptExecutor,
      FindsById, FindsByClassName, FindsByLinkText, FindsByName,
      FindsByCssSelector, FindsByTagName, FindsByXPath,
      HasInputDevices, HasCapabilities, Interactive, TakesScreenshot,
      HasVirtualAuthenticator {
  
  private static final Logger logger = Logger.getLogger(RemoteWebDriver.class.getName());
  private Level level = Level.FINE;
  private ErrorHandler errorHandler = new ErrorHandler();
  private CommandExecutor executor;
  private Capabilities capabilities;
  private SessionId sessionId;
  private FileDetector fileDetector = new UselessFileDetector();
  private ExecuteMethod executeMethod;
  private JsonToWebElementConverter converter;
  private RemoteKeyboard keyboard;
  private RemoteMouse mouse;
  private Logs remoteLogs;
  private LocalLogs localLogs;