## 🚀 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!");
```
String.format(
                "{Using=%s, value=%s}",
                command.getParameters().get("using"),
                command.getParameters().get("value")));
      }
      ex.addInfo(WebDriverException.DRIVER_INFO, this.getClass().getName());
      if (getSessionId() != null) {
        ex.addInfo(WebDriverException.SESSION_ID, getSessionId().toString());
      }
      if (getCapabilities() != null) {
        ex.addInfo("Capabilities", getCapabilities().toString());
      }
      throw ex;
    }
    return response;
  }
  protected Response execute(String driverCommand, Map<String, ?> parameters) {
    return execute(new CommandPayload(driverCommand, parameters));
  }
  protected Response execute(String command) {
    return execute(command, ImmutableMap.of());
  }
  protected ExecuteMethod getExecuteMethod() {
    return executeMethod;
  }
  @Override
  public void perform(Collection<Sequence> actions) {
    execute(DriverCommand.ACTIONS(actions));
  }
  @Override